I often come across the phrase "build bridges" and I'm keen to know the origin of this phrase.
I've done a lot of research on the Internet (plus in some books). Neither [Theidioms.com]( theidioms.com/build-bridges nor Phrases.org.uk have anything useful.
Assuming that the question here is about the origin of use of "burning bridges" in a figurative sense, I note one example from 1886, although it may not be the same one that FumbleFingers mentions in a comment beneath the posted question as the full OED's first such citation. From George Fisher, "Catholicity—True and False: Sermon," in Minutes of the National Council of the Congregational Churches of the United States (October 13–20, 1886):
Follow down the course of history from the apostolic age, and you will see that there has always existed, under diverse names and types, a party that may be styled the Broad Church. To connect the natural with the supernatural; to show that the supernatural is not the anti-natural; to bring out the consonance of faith and reason; to lay hold of whatever is true and valuable in the religions of the heathen, and in the philosophy and culture which have grown up on the soil of nature; to stand at the door of the Church and take care that none worthy to be called disciples are kept out; to soften the asperities of intellectual strife, and to build bridges between discordant sections of the Christian family—these have been the aims of the Broad Church.
Related searches, however, turn up several even earlier figurative matches for the phrase. From Alice Carey, "Bridges," in Poems of Alice and Phoebe Carey (1850):
My friend, wilt thou lend me thy counsel? / And then, if thou wilt, we will strive / O'er the river of death to build bridges, / That souls may o'erpass it and live.
From a letter to the editor dated January 21, 1850, from Thomas Shorter of London, in Cooper's Journal: Or, Unfettered Thinker and Plain Speaker for Truth, Freedom, and Progress (February 2, 1850):
Men co-operate to construct canals, build bridges, establish railways,—why should not men of Progress also co-operate to build bridges for thought, railways for intelligence, and aid the growth of Institutions for the formation of higher and better characters?
From a translation of K.E. von Baer, Fragments Relating to Philosophical Zoology, in Scientific Memoirs, Selected from the Transactions of Foreign Academies of Science, and from Foreign Journals: Natural History (1853):
Just as incomprehensible is the alliance between Echinoderms and Mollusks.
Do not these attempts to build bridges between two distant countries proceed from the endeavour to make each a link in a chain?
This is a compliment as to what Christianity has done, and a falsehood respecting what it has become; for we need to build more arches, and bridges are not "obstructions;" so that, if Christianity has built a bridge for England, it will keep it in repair, and build bridges in every other land, while infidelity shall be "struck away.”
From Grinnell, "A Beautiful Simile," in the [New York] Advocate and Family Guardian (July 15, 1861):
I noticed those huge bolts [anchoring a railway bridge across the Cheat River] driven into the solid rock on each side of the ravine, and thought what a good illustration it seemed of our union with Christ. We all build bridges over life and death, we equally hope these will prove secure.
And from A Citizen of the United States, Political Opinions (1865):
An infinite reform would be wrought by dividing the whole number of public offices by three and multiplying the terms and the salaries by the same number. The effect on the American Congress would be equally happy and astonishing. It has become impossible for Congress to deliberate : it can act with its present numbers, only like a board of supervisors, through committees whose chief business is to shirk personal responsibility, cover up the common ignorance and incompetency, and build bridges for the passage of every species of legislative speculation.
These early instances range from metaphorical bridges over metaphorical rivers, tied closely to the model of actual bridges and actual rivers, to figurative bridges that are more concerned with the idea of establishing a connection or passageway than with what flows or lies beneath them. Several focus on religious themes, but others involve secular connections—bridges for thought in 1850, connections between distantly related phyla in 1853, and passageways for legislative speculation in 1865.
