Owing to space limitations, I focus in this answer on a rather narrow subset of questions:
- How common were the expressions "highway to hell" and "highway to heaven" in the period before 1700?
- How common were they in the period before 1600?
- How were these expressions understood in the pre-1600 period?
EEBO data on 'highway/high-way/high way/high waie/high road to hell/hel'
Early English Books Online searches find 86 unique instances of "highway to hell" (in various spellings). Here are the number of unique occurrences of each variant and the years of publication of each instance:
highway to hell: 7 unique instances (1618, 1621, 1628, 1628, 1646, 1658, 1674)
high-way to hell: 28 unique instances (1616, 1630/1639, 1633, 1640, 1643, 1651, 1656, 1657, 1657, 1657, 1657, 1658, 1660, 1660, 1661, 1661, 1662, 1667, 1667, 1673, 1677/1678, 1677/1681, 1677/1684, 1680, 1683, 1687, 1689, 1696)
high way to hell (43 unique instances (1589, 1592/1596, 1598, 1599, 1601, 1601, 1603, 1604, 1611, 1613, 1615, 1615, 1616, 1619, 1620, 1621, 1622/1624, 1622/1630, 1623, 1628, 1630, 1635, 1636, 1641, 1642, 1651, 1653, 1653, 1655/1657, 1656, 1657, 1658, 1662, 1663/1664, 1665, 1672, 1673/1679, 1675, 1677, 1678, 1683/1685, 1689, 1697)
high way to hel: 2 instances (1572, 1595)
high waie to hell: 2 instances (1581, 1649)
high road to hell: 4 instances: 1662, 1668, 1695, 1696
Total before 1700 = 86; total before 1600 = 7
EEBO data on 'highway/high-way/high way/high waie/high vvay/high-road to heaven/heauen'
Here is how the 138 unique occurrences of the variant spellings of "highway to heaven" are distributed, along with the year of publication of each occurrence:
highway to heaven: 11 unique instances (1599/1629, 1624, 1632, 1632/1641, 1635, 1635/1680, 1645, 1656, 1675, 1677, 1697)
highway to heauen: 6 unique instances (1590, 1595, 1616, 1617, 1620, 1623)
high-way to heaven: 34 unique instances (1633, 1634, 1636, 1636/1650, 1639/1640, 1651, 1654, 1654, 1654, 1657, 1657, 1658, 1658, 1659, 1660, 1660, 1660, 1660, 1661, 1661, 1662, 1663, 1664, 1665, 1667, 1674, 1679, 1679, 1681, 1682, 1685, 1691–1692, 1695, 1698)
high-way to heauen: 6 unique instances (1610, 1617, 1619, 1620, 1620, 1629)
high-vvay to heauen: 1 unique instance (1609)
high way to heaven: 27 unique instances (1584, 1591/1595, 1599/1605, 1622, 1625, 1632, 1636, 1640, 1641, 1642, 1643, 1644, 1648, 1650, 1657, 1658, 1660, 1661, 1665, 1670, 1678, 1679, 1681, 1683, 1683, 1687, 1694)
high way to heauen: 46 unique instances (1553/1564, 1554/1583, 1554/1583, 1570, 1578, 1581, 1581, 1581, 1583, 1583, 1589, 1592, 1593, 1594, 1595, 1595/1606, 1597, 1597, 1599, 1600, 1601, 1602, 1603, 1603, 1604, 1606, 1607, 1608, 1609, 1609, 1612, 1615, 1616, 1617, 1618, 1620, 1622, 1622/1630, 1624, 1624, 1625, 1626, 1630, 1631, 1632, 1654)
high waie to heuen: 2unique instances (1581, 1581)
high vvay to heaven: 1 unique instance (1597)
high vvay to heauen: 2 unique instances (1620, 1663)
high-road to heaven: 2 unique instances (1654, 1699)
Total before 1700 = 138; total before 1600 = 27
Although I removed all duplicate occurrences of the same text within a particular search, in some instances a variant spelling of the same instance of an expression turned up in a different edition or source and so may have been counted more than once. For example, the instance of "highway to heaven" in John Bradford's 1554 letter to his mother and brethren appears in at least three different spellings in at least four different books (including Foxe's Martyrology). I have tried to weed out obvious duplicates across different spellings as well—since they aren't really unique instances of the expression—but some undoubtedly have slipped through.
Still, I think it probable that the unique EEBO matches for "highway to heaven" and its variants before 1700 number at least 125, whereas the unique EEBO matches for "highway to hell" during the same period do not number more than 86.
In assigning a year to each instance of the expression, I have primarily relied on the publication date that EEBO identifies. In cases where the author died one or more years prior to publication of the book cited, I have included the year of the author's death as part of a dual year citation. In instances where the book is a translation from another language, I have not included the date of original publication (if known) or the year of the author's death, on the theory that the translation the expression may be the translator's invention, rather than a literal translation of the original text's wording. For example, a 1654 translation of Marguerite of Navarre's Heptameron includes the following sentence:
Madam, For the time to come trust no more to such Hypocrites, I thought I had my Daughter in the High-way to Heaven, and the Suburbs of Paradise, and I have put her into Hell, and into the Hands of the worst Devils that ever were; ...
I have associated this instance with the year 1654, even though Marguerite died in the year 1549.
Usage of 'high way to hel[l]' in the 1500s
As noted above, EEBO searches turn up seven unique instances of the expression "high way to hell [or hel]" in texts published before 1600. I reproduce six of them, in chronological order, below.
From John Leslie, A Treatise of Treasons against Q. Elizabeth, and the Croune of England Diuided into Two Partes... (1572):
And can these two Religions be called one in effect, wherof the one teacheth that to be Idolatry, and the high way to hel: that the other doth adore, as ye chiefest outwarde Honour, Sacrifice, & seruice, that man can doe, or geue to God in this life?
From Thomas Lupton, A Dreame of the Diuell and Diues Most Terrible and Fearefull to the Seruantes of Sathan, but Right Comfortable and Acceptable to the Children of God (1589):
Theophilus. Though you in that case made no account of the diuell: yet doubtlesse, the diuell made some account of you.
Eumenides. Bee sure of that, yet I knowe certainely hee is deceiued, but if God had made no more account of mee then I did of my selfe: the diuell had not bin so deceiued of me as he is, nor I so out of his daunger as I am: for I was in the very high way to hell, & none went faster to the diuel then I: though you & diuers other willed me to forsake that way, but all that would not serue.
From Anthony Copley, Wits Fittes and Fancies Fronted and Entermedled with Presidentes of Honour and Wisdome (1595):
A Spanish Frier hauing granted vnto him a Bishopricke in India: Hee thus bespake the Emperours Secretarie, that drewe the assignation. Sir, because I know how daungerous a thing a Bishopricke is to one that knowes not howe to discharge his pastorall dutie therein as hee ought, and knowing withall my owne insufficiencie in that behalfe, I am verilie of opinion, that for me to be a Bishop were my high way to hel. And in sooth to go to hell by India is a great way about: Wherfore I pray you assigne me some neerer Sea, or none at all.
From W. Jones, "The Printer to the Christian Reader," in John More, A Liuely Anatomie of Death Wherein You May See from Whence It Came, What It Is by Nature, and What by Christ (1596):
I thought good to present you with this Anatomie of Death, that in the middest of your delightes, you may take a view of him, who will in the ende, cut off all your delights. Accept it as I import it, the Pawne of my good desire to pleasure you, and Bill for your assurance, to receaue greater things at my hand, when opportunitie shall serue: in the meane time, as you tender the health of your body, so likewyse care for the health of your soule: remembring, that Death to the wicked, is the high way to Hell: but Death to Gods chyldren, is the path-way to Heauen.
From George Gifford, "Sermon 1," in Foure Sermons vpon Seuerall Partes of Scripture (1598):
O how can men be saued while they stand in this estate, being either high minded, or trusting in vncertaine riches! Is not the way to heauen vnto them as the eye of a small needle is vnto an huge Camell? This is the very high way to hell, euen the broad way in which they walke: let them therefore harken what vertues the holie Apostle calleth them vnto, when they haue renounced and forsaken those two most pestiferous vices, which make the way to heauen vnpassable to them: the first is, that they trust in the liuing God.
From Edward Topsell, "The Eleuenth Sermon," in Times Lamentation: or An Exposition on the Prophet Ioel, in Sundry Sermons or Meditations (1599):
Oh would not this grieue the heart of man, to see so many, so great, so aged, so wealthie, so tender to abhorre all mortification, and the sorrowfull way to life; but to embrance all condemnation, and the ioyfull high way to hell fire. Know you not that ease slayeth the foolish, and the restie oxe is prepared for the slaughter? why then do you thirst still for more pleasure, and hunger after more vanitie?
Lupton's 1589 instance is interesting because it explicitly uses the expression "high way to hell" in the context of traveling "faster" to the devil. Jones's 1596 instance is striking because it contrasts the "high way to Hell" with the "path-way to Heauen," suggesting that the former carries far more traffic than the latter. And finally, Gifford's 1598 instance is noteworthy for emphasizing that "the high way to hell" is indeed a "broad way," whereas, for the rich (invoking the biblical warning), the passage to heaven is as difficult as entering through the eye of a needle would be to a camel.
Usage of 'highway to heaven' in the 1500s
Of the 28 unique matches for "highway to heaven" from the 1500s, the vast majority spell "high way" as two words and "heaven" as "heauen." Nevertheless, EEBO does report a smattering of instances of "highway," "heaven," and "heavven." Here are the earliest fifteen instances of the expression, ordered chronologically.
From a letter by John Bradford to Richard Hopkins (July 4, 1553), in Certain Most Godly, Fruitful, and Comfortable Letters of Such True Saintes and Holy Martyrs of God, as in the Late Bloodye Persecution Here Within This Realme, Gaue Their Lyues for the Defence of Christes Holy Gospel Written in the Tyme of Their Affliction and Cruell Imprysonment (1564):
Cal vpon God therfore now in your trouble and he wil heare you, yea deliuer you in such sort as most shall make both to his & your glory also. And in this calling I hartely pray you to praye for me your fellowe in affliction. Now we be both going in ye high way to heauen, for by many afflictions must we enter in thether: whether god bring vs for his mercies sake, Amē, Amē.
From a letter by John Bradford to his mother (1554[?]) in John Foxe, Actes and Monuments of Matters most Speciall and Memorable, Happenyng in the Church, Book 1 (1583):
I am at this present in prison sure enough for starring, to confirme that I haue preached vnto you: as I am ready (I thanke God) with my lyfe and bloud to seale the same, if god vouch me worthy of that honor. For good mother and brethren, it is a most speciall benefite of God, to suffer for his names sake and gospel, as now I doe: I hartily thanke him for it, and am sure that with him I shal be partaker of his glory, as Paule sayth? If we suffer with hym we shall raygne with him. Therfore be not faynt harted, but rather reioyce, at the least for my sake which now am in ye right and high way to heauen: for by many afflictions we must enter into the kingdome of heauen.
From a letter by John Bradford to Lord Russell (1554[?]) in John Foxe, Actes and Monuments of Matters most Speciall and Memorable, Happenyng in the Church, Book 1 (1583):
For though the reason or wisedome of the worlde thinke of the Crosse according to theyr reach and according to theyr present sence, and therefore flyeth from it as from a most great ignominye and shame: Yet Gods Scholers haue learned otherwise to thinke of the Crosse, that is the frame house in the which God frameth his children lyke to his sonne Christ: the Fornace that fineth Gods golde: the high way to Heauen: the Sute and Liuery that Gods seruauntes are serued withall: the earnest and beginning of all consolation and glory.
From a biographical sketch of Demosthenes appended to a 1570 translation of Demosthenes, The Three Orations of Demosthenes Chiefe Orator Among the Grecians, in Fauour of the Olynthians:
So that whereas there be two wayes of loue offered to euery one at his first entrie, to tread in, the one sauage, rude, and wicked, being the very path to hell, death, and damnation: the other, godly, plaine, right, and honest, being the high way to heauen, and al the ioyes that may be, the which way entiseth all good men to it, through the beautie thereof, & draweth all them with an heauenly traunce or motion of minde, that are borne of Gods race: ...
From a 1578 translation of Caspar Huberinus, A Riche Storehouse, or Treasurie, for the Sicke, Full of Christian Counsels Holesome Doctrines, Comfortable Persuasions, and Godly Meditations, Meete for All Christians, Both in Sicknesse and in Health:
The second [reason for writing this book], from Christian loue and [cha]ritie, the bond of all perfection, where[to] the souldiers of Christe are specially [u]rged: which then (indeede) most natu[ral] appeareth, when we, (perceiuing the bodies of our brethren and sisters so infeebled and consumed with sicknesse, or otherwise by lawe, through desert of death, iudged and condemned, that they are past all temporall recouerie,) succour neuerthelesse their appassionate soules, with comfortable restorities of the spirite, that they may the more willingly forsake the wildernesse of this worlde, and constantly trauell the high way to heauen.
From a 1581 translation of Stefano Guazzo, The Ciuile Conuersation ..."
Annibal. If there be nothing else to kéepe her [Queen Elizabeth] from heauen but her religion, no doubt but she shal goe thither so soone as God shal plague her subiects so sore as to take her from them: For I can tell you this, that the most learned men in the worlde are of this opinion, that her religion is the very high way to heauen.
From Abraham Fleming, The Diamond of Deuotion Cut and Squared into Sixe Seuerall Points... (1581):
Who so therefore is desirous to taste of the fruite of the trée of life, and to drinke of the pleasant running riuers of rest: who so (I saie) longeth after true happines, and faine would sée good daies, let him endeuour to the vttermost of his might, to tame and bridle his wandering desires, which if they be not brought vnder, and constrained to grone vnder the yoke of subiection, he shall haue his mind so bent vpon transitorie vanities, and his wilso wedded to this wicked world, that the light of his vnderstanding being put out, he shall neuer finde the footepath of faith leading the high waie to heauen. In this respect therefore let vs learne what is to be done?
...
Consider these circumstances, and account them all Gods blessings, ascribe nothing to thy selfe, which art a lumpe of sin, but attribute all vnto Gods prouidence, which hath wrought all in all, be thankefull for it, and giue the glorie to his eternall name. This is the footepath of faith, which leadeth the high waie to heauen.
...
My thoughts are not your thoughts, neither are my waies your waies, saith the Lord. As if he should say, your thoughts are vncleane, corrupt, earthie, vile, vnpure, vnperfect, sinfull, abominable, wicked, variable, momentanie, vncertaine, wauering: for they are ingendered in your hearts, which are nothing else but a sinkehole of sinfulnesse, a dunghill of naughtinesse, a puddle of filthinesse, a lake of vncleannesse, and what is worst that is your heart. As for your waies, they are no better. Thus by an antithesis, or opposition, the Lord teacheth vs what his waies are, euen the waies of truth, righteousnesse, puritie, and perfection: wherein who soeuer walketh, no doubt, he is in the high way to heauen, and treadeth the footepath to felicitie.
...
[I]n this waie [the way of the Lord] whosoeuer walketh, the moone shall not hurt him by night, nor the sunne annoie him by day: the pestilence shall not touch him, the arrowes of the hunter shall not wound him, he shall not stumble, nor hit his foot against a stone, the Lord will ouershadowe him with the shield of safetie, the Lord will be his defence, his buckler, his speare against all his enimies, no lightning from aboue, no earthquake beneath, no consuming fire on this side, no raging sea on that, no element, no planet, finallie, no creature shall do him anie harme. This honor will the Lord vouchsafe all such as walke in his waie, which is the waie of life, the high waie to heauen, and the footepath to felicitie.
From a 1581 translation of Jean de Cartigny, The Voyage of the Wandering Knight:
Were the Husband-man any better than a foole, if hée should hope in Harurst to reape Corne of his ground, where he hath sowed no seede, when season serued? Euen so is that man meruailously misinformed, that thinketh to atchieue perfect felicitie, or to reape true blessednesse, hauing not first fallowed his field with Uertue, Good déedes, Faith, Hope and Charitie, which is the High way to Heauen.
From John Foxe, Actes and Monuments of Matters most Speciall and Memorable, Happenyng in the Church, Book 2 (1583):
All the holy Prophetes, Christ and hys Apostles suffered such afflictions not for euill doing, but for preaching Gods word, for rebuking the world of sinne, and for theyr fayth in Iesus Christ. This is the ordinance of GOD (my Frendes) this is the high way to heauen, by corporall death to eternall life: as Christ sayth, he that heareth my woordes and beleeueth in him that sent mee, hath eternall life, and shall not come into iudgement, but is escaped from death to life.
From Robert Parson, A Booke of Christian Exercise Appertaining to Resolution, That Is, Shewing How That We Should Resolve Our Selves to Become Christians Indeed (1584):
Lastlie, if Gods eternal wisdome hath so ordained and appointed, that this shal be the badge and liverie of his Son; the high way to heaven, under the standard of his crosse: then ought we not to refuse this liverie; nor to flie this way, but rather with good Peter and Iohn to esteem it a great dignitie, to be made woorthy of the most blessed participation therof.
From Thomas Lupton, A Dreame of the Diuell and Diues Most Terrible and Fearefull to the Seruantes of Sathan, but Right Comfortable and Acceptable to the Children of God (1589):
Eumenides. ... Diues furthermore sayde, O how hapy are they that are on the earth, for that they haue time to repent, and to liue, godly, to whom the Deuill answered: yea, but how vnhappy are they that will not repent, but liues most abhomiably and wickedly. Then saide Diues, if their hearts were not hardned and their mindes bewitched, they woulde not doe so, they I perceiue make little account of that precious Iewell the Gospell, which teacheth them the high way to Heauen, and so to shune the fiery flames of hell.
From Richard Harvey, A Theologicall Discourse of the Lamb of God and His Enemies... (1590):
This place is the common highway and passage from Syria to Palestina by ferry, and therefore a most populous and much frequented place, saith Gualter: this is the place, which the Israëlites went through right ouer Iericho with their puissant & triumphant captaine Iosua, while the water of Iordane was miraculously driuen backward on the right hand and on the left, and therefore a famous and wonderful place: Iosua c. 3. v. 16: this is the place, where the inhabitants of mount Ephraim tooke the princes of the Madianites by the appointment of Gedeon, both Oreb and Zeb, and therefore a victorious and renowmed place: Iudges c. 7. v. 24, 25: a place both for the former excellencie and present vse most fit for Iohns baptisme, wherby we enter the highway to heauen, in which we tread the path that leadeth vs against our spiritual enimies, & by which we ouercome the kings of this worlde, and the chiefest in the waies of the ayre.
From Henry Smith, "Iacobs Ladder, or The High Way to Heauen: Being the last sermon that Master Henry Smith made" (1591/1595):
Death also is dreadfull: what then? but to whom I pray thee? euen to the man that hath his trust in his riches, or hath no hope of a better life: but to him that beleeueth in Christ, it is become through the power of the death and obedience of Christ, a speedie passage to eternall life. We endure many dreadfull and dangerous thinges, and runne through fire & water, and alfor a corruptible crowne: And why should wee not with patience and prayer passe through this, which is the very high way to heauen? Besides, hell is horrible[:] Neither will I deny that: but still I demaund to whom it is so?
From Robert Greene, Greenes, Groats-worth of Witte, Bought with a Million of Repentance (1592):
Nay then, saide the Player, I mislike your iudgement: why, I am as famous for Delphrigus, & the King of Fairies, as euer was any of my time. The twelue labors of Hercules haue I terribly thundred on the Stage, and plaid thrée Scenes of the Deuill in the High way to heauen.
And from Barnabe Rich, Greenes Newes Both from Heauen and Hell: Prohibited the First for Writing of Bookes, and Banished out of the Last for Displaying of Conny-Catchers (1593):
When pittiles Death had sommoned my soule to leaue his transitory estate, infusing his frosty humour through all the parts of my body, leauing my breathles corps a fitte pray for the sepulcher, my deceased ghost wandring now to and fro in many obscure & vnknown waies, desirous to find a place of rest, at the length lighted into a straight and narrow tract, so ouergrowne with bryers & brambles, that there was almost no passage left, and as it should séeme vnto me, did lead vnto some ruinated place, where all former trade & traffique was decayed, the solitarines wherof (me thought) was best befitting & answerable to my humor: so that with great difficulty scratching through the bushes, it brought me at the length to the foote of a mighty stéepe Hil, whose height I was not able to discerne, but by the vnpleasantnes of y[e] path, leading ouer monstrous Rocks craggy & ill fauoured to passe, I perceiued it to be the high way to Heauen. ...
...
Hée [one of Greene's companions] breaking out into sundry passions, some-times raging against the Myller, saying that he was but an ignorant and a lying Heretique: then calling to his memory the long tyme he had spent in seeking of Purgatory, hee beganne as vehemently to rayle against the Pope, and as bitterly to exclaime against hys Iesuites and Seminaries, that had promised to instruct hym in the high way to Heauen, and directlie sent him the verie next way to Hell.
The most noteworthy thing about these instances is that most of them treat the "highway to heaven" in serious terms as an accurate metaphor for the way to reach eternal rest. Many of them treat martyrdom (or at least affliction) as a straight and fair means to salvation—indeed, one that believers should whole-heartedly embrace. Only Barnabe Rich's 1593 piece treats the notion of the highway to heaven with some degree of irony, presenting it as an unpleasant path "leading ouer monstrous Rocks craggy & ill fauoured to passe."
I also note that Thomas Lupton's 1589 Dreame of the Diuell and Diues contains references to both the "high way to hell" (the second earliest such mention in EEBO's search results) and the "high way to Heauen" (the eleventh such mention in EEBO's search results).
Conclusions
The early matches from searches of the Early English Books Online database confirm that both "highway to hell" and "highway to heaven" were well established metaphors by 1600, although the latter was considerably more common than the former. In fact, "highway to heaven" is more common than "highway to hell" not only in the period 1550–1559 but also in the period 1600–1699 (albeit by a much smaller proportion in the second time period).
As one might expect, the "highway to heaven" was generally presented as entailing self-discipline, privation, and (often) suffering, whereas the "highway to hell" was associated with luxury, immoderate pleasures, and wicked self-indulgence. I would caution, however, against imagining that the "highway to heaven" was understood ironically or oxymoronically. Most sixteenth-century writers who alluded to the "highway to heaven," I think, viewed it as indeed a straight road to salvation to be willingly traveled; if anything, these writers tended to play down the difficulty and self-sacrifice involved in keeping to it, focusing instead on the present spiritual joys and future rewards to be had from righteousness.
In both cases, I understand "the highway" as signifying "the direct route"—whether to hell or to heaven.
