Purgatory is the state of purification after death for those who die in God's grace but are not yet fully purified. It is not a 'second chance' for the damned, but a process of final cleansing for souls destined for heaven. The doctrine is based on 2 Maccabees 12:46 ('It is a holy and wholesome thought to pray for the dead, that they may be loosed from sins'), 1 Corinthians 3:15 ('saved, but only as through fire'), and the Church's longstanding tradition of praying for the dead. Catholics can help souls in purgatory through prayer, Mass offerings, indulgences, and charitable works. Purgatory will end at the Last Judgment, when all purified souls enter heaven.