Born at the beginning of the second century, Justin was raised in a pagan family. He was student of philosophy who converted to the Christian faith and became a teacher in Ephesus and Rome. After refusing to make pagan sacrifices, he was arrested, tried and executed, along with six other believers. The official Roman court proceedings of his trial before Rusticius, a Roman prelate, document his confession of faith. The account of his martyrdom became a source of great encouragement to the early Christian community. Much of what we know of early liturgical practice comes from Justin.
The Treasury writing today quotes from the First Apology:
We hold our common assembly on Sunday because it is the first day of the week, the day on which God put darkness and chaos to flight and created the world, and because on that same day our Savior, Jesus Christ, rose from the dead.
Almighty and everlasting God, You found Your martyr Justin wandering from teacher to teacher, searching for the true God. Grant that all who seek for a deeper knowledge of the sublime wisdom of Your eternal Word may be found by You, who, sent Your Son to seek and to save the lost; through Jesus Christ, our Lord...