He is noted for his imitation of Cato the Younger, his espousal of the Cynic philosophy, and for his appearance as the Poet in William Shakespeare's play Julius Caesar.
[2] According to Plutarch, Favonius stood to be chosen aedile, and was like to lose it; but Cato, who was there to assist him, observed that all the votes were written in one hand, and discovering the cheat, appealed to the tribunes, who stopped the election.
[8] Despite his "wild, vehement manner",[7] Favonius was capable of acts of humility, such as he performed to Pompey when he entertained Deiotarus I of Galatia aboard ship.
When Caesar returned from his praetorship in Spain in 59 BC and successfully stood for consul, he allied himself with Pompey (to whom he gave his daughter Julia in marriage) and Clodius.
[11] A party led by Cicero, Lucullus and Bibulus, to which Cato and Favonius allied themselves, opposed these measures, but eventually either swore the oath or abstained.
According to Plutarch, The one who was most successful in persuading and inducing him [Cato] to take the oath was Cicero the orator, who advised and showed him that it was possibly even a wrong thing to think himself alone in duty bound to disobey the general will; and that his desperate conduct, where it was impossible to make any change in what had been done, was altogether senseless and mad; moreover, it would be the greatest of evils if he should abandon the city in behalf of which all his efforts had been made, hand her over to her enemies, and so, apparently with pleasure, get rid of his struggles in her defence; for even if Cato did not need Rome, still, Rome needed Cato, and so did all his friends; and among these Cicero said that he himself was foremost, since he was the object of the plots of Clodius, who was openly attacking him by means of the tribuneship.
"[4] Upon hearing the news that of the members of the Triumvirate, Caesar was to be given a fresh supply of money, and Pompey and Crassus were to be consuls again the following year, Favonius, "when he found he could do no good by opposing it, broke out of the house, and loudly declaimed against these proceedings to the people, but none gave him any hearing; some slighting him out of respect to Crassus and Pompey, and the greater part to gratify Caesar, on whom depended their hopes".
According to Suetonius, "Marcus Favonius, the well-known imitator of Cato, saluted Antonius respectfully as Imperator when they were led out in chains, but lashed Augustus to his face with the foulest abuse.
[18] Sarmentus was the subject of Quintus Dellius' complaint to Cleopatra that while he and other dignitaries were served sour wine by Antony in Greece, Augustus' catamite was drinking Falernian in Rome.
According to Plutarch, Marcus Favonius, who had been an ardent admirer of Cato, and, not so much by his learning or wisdom as by his wild, vehement manner, maintained the character of a philosopher, was rushing in upon them, but was hindered by the attendants.
And though he was a senator, yet, thinking that one of the least of his excellences, he valued himself more upon a sort of cynical liberty of speaking what he pleased, which sometimes, indeed, did away with the rudeness and unseasonableness of his addresses with those that would interpret it in jest.
Favonius, breaking by force through those that kept the doors, entered into the chamber, and with a set voice declaimed the verses that Homer makes Nestor use – "Be ruled, for I am older than ye both."
At this Cassius laughed; but Brutus thrust him out, calling him impudent dog and counterfeit Cynic; but yet for the present they let it put an end to their dispute, and parted.
Brutus called out aloud and told him he was not invited, and bade him go to the upper couch; but he violently thrust himself in, and lay down on the middle one; and the entertainment passed in sportive talk, not wanting either wit or philosophy.