It is TRUE that The Apology of Trypho on Behalf of Christians (c.125), written by Trypho, was perhaps the first formal Christian apology written after the composition of the NT books.
Explanation:
The setting is presented as a chance meeting between Justin and Trypho in Ephesus. Justin had just converted to Christianity from a philosophical background and Trypho had just fled the disturbances in Judea.
When Justin suggests to Trypho to convert to Christianity, the dialogue becomes animated. Trypho criticizes Christians on a number of grounds, and Justin provides answers to each criticism.
In the opening of the Dialogue, Justin relates his vain search among the Stoics, Peripatetics, and Pythagoreans for a satisfying knowledge of God; his finding in the ideas of Plato wings for his soul, by the aid of which he hoped to attain the contemplation of the God-head; and his meeting on the sea-shore with an aged man who told him that by no human endeavor but only by divine revelation could this blessedness be attained, that the prophets had conveyed this revelation to man, and that their words had been fulfilled. Of the truth of this he assured himself by his own investigation; and the daily life of the Christians and the courage of the martyrs convinced him that the charges against them were unfounded.
So he sought to spread the knowledge of Christianity as the true philosophy.
