Catechism of the Catholic Church

But there is more. Jesus links faith in the resurrection to his own person: "I am the Resurrection and the life." It is Jesus himself who on the last day will raise up those who have believed in him, who have eaten his body and drunk his blood. Already now in this present life he gives a sign and pledge of this by restoring some of the dead to life, announcing thereby his own Resurrection, though it was to be of another order. He speaks of this unique event as the "sign of Jonah," the sign of the temple: he announces that he will be put to death but rise thereafter on the third day. (646)