When we die, Catholics believe that our life and all our choices become clear to us. It's as if our life passed before our eyes. In that moment we judge ourselves: if we die in the state of grace, and if we are ready to see God face to face, then we are welcomed into heaven by the Lord, and we are numbered among the saints. However, most of us, strange mix of saint and sinner that we all are, will not be quite ready to meet God in our death. For us, purgatory is a temporary period of preparation. This is a time of joyful waiting, because we know that we are getting ready to see God. If however, we see that the sum of our choices was against God and God's people, we choose an eternity apart from God's love: hell, which is eternal and without joy. FOREVER. Is there a hell? YES. There must be, if we believe that God is all-just. But do we know for sure that anyone is in hell? The church has never answered that question, because we also believe in a God who is all-merciful. The real question is this: Is God more merciful or more just? Remember that God does not damn any of His creatures to hell. We damn ourselves, by our sinful actions, our lack of love, and our stony hearts. This choice of ours, to spend eternity with God or apart from Him, is known as personal judgment.
At the end of time, we also believe that Christ will return and then will judge all of creation. This is called final judgment. In that moment, evil will be conquered by Christ's grace forever, and the righteous will be raised up from the dead. Every Sunday during the Creed, we say, "We believe in the resurrection of the dead." The righteous dead from the beginning of time will be reunited with their glorified bodies to be with the Risen Christ forever.