In it, Justin Martyr passionately defends the morality of the Christian life and provides various ethical and philosophical arguments to convince the Roman emperor Antonius to abandon the persecution of the Church. Further, he indicates, as St. Augustine would later, regarding "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) as unknowing Christians.
(Origin of the Bible handout by my small group leader, February 8, 2023. Summarized from Wikipedia. Page 4-5.)