The Catechism in Questions & Answers

186. What significance does the resurrection of Christ hold for mankind?

Jesus Christ is risen. As a result, believers have justified hope in their own resurrection and eternal life: “But now Christ is risen from the dead, and has become the firstfruits of those who have fallen asleep. For since by man came death, by Man also came the resurrection of the dead. For as in Adam all die, even so in Christ all shall be made alive” (1 Corinthians 15: 20-22).
Belief in the resurrection of Jesus is necessary because His resurrection shows that Jesus is the Saviour of the world (cf. 1 Corinthians 15: 14).

Saviour: see Question 108., also 110. et seq.