In Book One, Raphael relates his conversations with Cardinal John Morton to More and Peter Giles. In one particular conversation, Raphael describes a friar whom, offended by the words of a fool spoken in jest, begins to call that fool all kinds of terrible names. The friar justifies his actions with an allusion to King Solomon from the Bible in a situationally ironic moment:
"I would not act more wisely. For Solomon, that wisest of men, says Answer a fool according to his folly, just as I'm doing now. I'm showing him the pit into which he'll fall if he's not careful."
The friar quotes Proverbs 26:5. King Solomon is a wise and reputable judge from the Old Testament of the Bible, known for making fair decisions regarding problems that troubled his subjects. This allusion made by the friar is ironic, considering that his response to the fool is clearly irrational. The allusion also betrays the friar's arrogance. He believes himself morally superior to the fool, though he ends up replicating his actions.
On a larger societal level, the friar's actions can be taken as a reflection of various deficiencies in the clergy: he, of all people, should set a moral example for the ordinary citizens he serves. Instead, the friar resorts to bullying and lashes out in anger—two of the very things Jesus speaks out against in the Bible.
In the following conversation between Peter Giles and More at the beginning of Book One, Giles mentions two well-known adventurers, Ulysses and Palinurus, in addition to the philosopher Plato. He compares Raphael to these men:
"At first glance I suspected [Raphael] was a ship's captain."
"Then you are right off target," [Peter Giles] said, "for he hasn't sailed like Palinurus, but rather like Ulysses, or, better still, Plato. For this man, Raphael as he's called, his family name being Hythloday, is far from incompetent in Latin and is especially well-versed in Greek."
Alluding directly to the lore (in the case of the very fictional Ulysses and Palinurus) and works (in Plato's case) of these men, Giles establishes Raphael's character as tending towards the more adventurous, philosophical, and intellectual. Palinurus is the coxswain and steersman of Aeneas's ship in Virgil's Aeneid. By contrasting Raphael with Palinurus, Giles is claiming that Raphael is not simply a sailor or navigator—he is a thinker and a philosopher of the most sophisticated kind. He therefore is more like Ulysses, whom Homer famously wrote about as a great hero. Perhaps more accurately, though, Giles decides that Raphael is most comparable to the famous Ancient Greek philosopher Plato, thus imbuing him with the respect one would show a legendary thinker.
What's more, Raphael's name itself is also a biblical allusion to the archangel Raphael, who's commonly associated with the power of healing. This is appropriate for Raphael's character, since he's a philosopher and student of how to best "heal" society's ills.