But, as we said above, wicked devils perpetrated these things. And we have learned that only those are deified who have lived near God in holiness and virtue; and we believe that those who live wickedly and do not repent are punished in everlasting fire.  – First Apology 21 (121 A.D)

St. Justin Martyr

And more than all other men are we your helpers and allies in promoting peace, seeing that we hold this view, that it is impossible for the wicked, the covetous, the conspirator, and for the virtuous to escape the notice of God, and that each man goes to everlasting punishment or salvation according to the value of his actions. For if all men knew this, no one would choose wickedness even for a little, knowing that he goes to the everlasting punishment of fire; but would by all means restrain himself, and adorn himself with virtue, that he might obtain the good gifts of God, and escape the punishments. – First Apology, 12 (151 A.D.)

We have learned from the prophets, and we believe it is true, that punishments, and chastisements, and good rewards, are rendered according to the merit of each man’s actions. If it is not so, then all things happen by fate, and nothing is in our own power. If it is fated that this man be good, and this other evil, the former is not meritorious nor the latter blameworthy. – First Apology, 43

Jesus shall come from heaven with glory, accompanied by his angelic host, when he shall raise the bodies of all men who have lived, and shall clothe the worthy with immortality, and shall send the wicked, endued with eternal sensibility, into everlasting fire with the wicked devils. – First Apology 52

Eternal fire was prepared for him who voluntarily departed from God and for all who, without repentance, persevere in apostasy. – Fragment in St. Irenaeus of Lyons, Against Heresies 5:26:2 (153 A.D.).