CCC 436 The word “Christ” comes from the Greek translation of the Hebrew Messiah, which means “anointed”. It became the name proper to Jesus only because he accomplished perfectly the divine mission that “Christ” signifies. In effect, in Israel those consecrated to God for a mission that he gave were anointed in his name. This was the case for kings, for priests and, in rare instances, for prophets.1 This had to be the case all the more so for the Messiah whom God would send to inaugurate his kingdom definitively.2 It was necessary that the Messiah be anointed by the Spirit of the Lord at once as king and priest, and also as prophet.3 Jesus fulfilled the messianic hope of Israel in his threefold office of priest, prophet and king.

CCC 1286 In the Old Testament the prophets announced that the Spirit of the Lord would rest on the hoped-for Messiah for his saving mission.4 The descent of the Holy Spirit on Jesus at his baptism by John was the sign that this was he who was to come, the Messiah, the Son of God.5 He was conceived of the Holy Spirit; his whole life and his whole mission are carried out in total communion with the Holy Spirit whom the Father gives him “without measure.”6

1 Cf. Ex 29:7; Lev 8:12; 1 Sam 9:16; 10:1; 16:1, 12-13; I Kings 1:39; 19:16.
2 Cf. Ps 2:2; Acts 4:26-27.
3 Cf. Is 11:2; 61:1; Zech 4:14; 6:13; Lk 4:16-21.
4 Cf. Isa 11:2; 61:1; Lk 4:16-22.
5 Cf. Mt 3:13-17; Jn 1:33-34.
6 Jn 3:34.