USCCB - Catechesis in the Catholic Church

Catechism of the Catholic Church

b. Para. 639: The mystery of Christ's resurrection is a real event, with manifestations that were historically verified, as the New Testament bears witness.
Para. 643: Given all these testimonies, Christ's Resurrection cannot be interpreted as something outside the physical order, and it is impossible not to acknowledge it as an historical fact. It is clear from the facts that the disciples' faith was drastically put to the test by their master's Passion and death on the cross, which he had foretold (Cf. Lk 22:31-32). The shock provoked by the Passion was so great that at least some of the disciples did not at once believe in the news of the Resurrection. Far from showing us a community seized by a mystical exaltation, the Gospels present us with disciples demoralized ("looking sad" [Lk 24:17; cf. Jn 20:19]) and frightened. For they had not believed the holy women returning from the tomb and had regarded their words as an "idle tale" (Lk 24:11; cf. Mk 16:11, 13). When Jesus reveals himself to the Eleven on Easter evening, "he upbraided them for their unbelief and hardness of heart, because they had not believed those who saw him after he had risen" (Mk 16:14).