There are lots of reasons the resurrection of Jesus is important. Here are SIX:
1. This is the GREAT SIGN that Jesus really is Son of God: Romans 1:4
2. This SIGN vindicates and validates all of Jesus’ ministry, including the promise he made in Matt 20:28.
3. Jesus’ resurrection is proof that we will be forgiven of our sins: Romans 4:25.
4. Jesus’ resurrection brought in the NEW CREATION.
J.I. Packer state is well: “Jesus’ resurrection was… not just a resuscitation of the ruined physical frame that was taken down from the cross for burial. It was, rather, a transformation of Jesus’ humanity… It was the creative renewing of his original body, the body that is now fully glorified and deathless (Phil. 3:21; Heb. 7:16, 24). The Son of God in heaven still lives in and through that body, and will do so forever.”
We see this also in Col 1:18 “Jesus is the firstborn of the dead” which CANNOT mean first to rise from the dead (Lazarus rose), but most mean Jesus’ rising is the 1st of the new creation.
5. If we are Christians, we are spiritually raised from the dead and united with Christ: Col 2:12.
6. The resurrection of Jesus assures us that we ourselves will one day be physically resurrected. Daniel 12:2