If I have 'read guides where people insist that...' then how do I use that in the passive voice?
'In guides I have read, it is insisted that...'? 'In guides I have read, it is insisted upon that..'?
Or is it something different?
Here X is the thing insisted. For example, X could be "visitors to Italy must try the delicious local pizzas".
You could say, "There has been insistence that X". Or "That X has been insisted".
And your structure also works, "... it has been insisted that X".
You can prefix or postfix any of my examples with "In guides that I have read", "In some guides", and so on. For example:
In guides that I have read, it has been insisted that X.
These are all acceptable, though some are awkward.
If you really wanted to, you could say it is insisted that and you would have the support of at least one citation from the OED (Oxford English Dictionary). It is insisted upon that, however, has no such support. In any case, both sound very formal and are unlikely to be used in contemporary English.
It depends on the exact sentence, specifically on whether the construction is "insisted that" or "insisted on"; your question mentions both.
Here are two examples:
I for myself would probably use an expression like
Grammatically, this may not be the correct way to transform into past tense. However, it seems to convey the meaning appropriately enough, assuming you are dealing with literary writing and not technical material.
Insist is an intransitive verb, and only transitive verbs may be Passivized, except under very special circumstances. Of which this is not one.
Semantically, insist means to make a statement (with optional That-clause) or to issue an order or demand for action (with optional gerund), but with the additional information that the statement was strongly affirmed by its speaker -- or the order strongly delivered, and probably repeated, and that the speaker was convinced of the truth of the statement or their authority and determination to see the action performed, and tried to convince the listener(s) of its truth or necessity.
Syntactically, insist requires a volitional human subject and takes two types of complements:
If the gerund is subjectless, the subject is interpreted to be the same as the subject of insist (i.e, insist on takes a Gerund with Equi-NP-Deletion)
The That-clause or gerund can be passivized, of course, if they're transitive:
But the only passive I can find for insist is with the preposition on
and only really works with a small (ideally pronoun) pre-Passive preposition object
Whether a particular predicate can be Passivized depends on a number of things, including transitivity, and a nascent transitive verb construct like insist on hasn't grown a whole lot of transitivity muscles yet -- just enough to support a pronoun, it seems.