In First Apology 12, Justin wrote that "each man goes to everlasting punishment or salvation according to the value of his actions (Gk: αἰωνίαν κόλασιν ἢ σωτηρίαν κατʼ ἀξίαν τῶν πράξεων)" (ANF 1:166).
According to Leslie William
Barnard in St. Justin Martyr: The First and Second Apologies,
Justin
puts the judgment, when men and women will be judged before the throne of God
according to their deeds, immediately after the second advent or at the close
of the millennium. Every person—the living and the dead—reaching as far back as
Adam will appear before the great assize. As Isaiah was sawn asunder so will
Christ divide the human race at the judgment (Dial. 120).