"By his power God raised the Lord from the dead, and he will raise us also." 1 Corinthians 6:14

I once saw an atheist online arguing that Jesus' sacrifice was null because he resurrected. For him, a real sacrifice requires that the person remain dead. In this view, Christianity would be completely false. However, this is not how historical Christianity is understood. It is necessary to understand some concepts to understand this issue.

Christ's sacrifice is not death itself, but the act of passing through death. Jesus, as he was and is God, could have remained in heaven, reigning over all. Jesus had no obligation whatsoever to sacrifice himself for us. He owes us no explanation. However, through an act of love, he descends from heaven and incarnates. In addition to developing a ministry of teaching, preaching, and miracles, he dies for us on the cross and remains dead for three days.

Therefore, his sacrifice was passing through death. He remained dead for three days and then resurrected. When he did this, he paved the way for the same to happen to us. We will die and our souls will go to paradise, but at Christ's return our bodies will be rebuilt and reunited with our souls. Christ's work encompasses the incarnation, death, and resurrection. Paul even says that if Christ has not been raised, our faith is futile. The resurrection is the foundation of Christian doctrine.