2 Maccabees 12:44-45

New Revised Standard Version, Anglicised Catholic Edition

⁴⁴ For if he were not expecting that those who had fallen would rise again, it would have been superfluous and foolish to pray for the dead. ⁴⁵ But if he was looking to the splendid reward that is laid up for those who fall asleep in godliness, it was a holy and pious thought. Therefore he made atonement for the dead, so that they might be delivered from their sin.