Justin Martyr, an early Christian apologist, is regarded as the foremost exponent of the Divine Word, the Logos, in the second century. He was martyred, alongside some of his students, and is venerated as a saint by the Catholic Church, the Anglican Church, the Eastern Orthodox Church, and the Oriental Orthodox Churches.

Most of his works are lost, but two apologies and a dialogue did survive. The First Apology, his most well known text, passionately defends the morality of the Christian life, and provides various ethical and philosophical arguments to convince the Roman emperor, Antoninus, to abandon the persecution of the Church. Further, he also indicates, as St. Augustine would later regarding the "true religion" that predated Christianity, that the "seeds of Christianity" (manifestations of the Logos acting in history) actually predated Christ's incarnation. This notion allows him to claim many historical Greek philosophers (including Socrates and Plato), in whose works he was well studied, as unknowing Christians.

Source: https://en.wikipedia.org/wiki/Justin_Martyr

St. Justin Martyr - c. 155 A.D.
First Apology 
St. Justin Martyr - c. 157 A.D.
Second Apology 
St. Justin Martyr - c. 160 A.D.
Dialogue with Trypho