CCC 536 The baptism of Jesus is on his part the acceptance and inauguration of his mission as God’s suffering Servant. He allows himself to be numbered among sinners; he is already “the Lamb of God, who takes away the sin of the world”.1 Already he is anticipating the “baptism” of his bloody death.2 Already he is coming to “fulfil all righteousness”, that is, he is submitting himself entirely to his Father’s will: out of love he consents to this baptism of death for the remission of our sins.3 The Father’s voice responds to the Son’s acceptance, proclaiming his entire delight in his Son.4 The Spirit whom Jesus possessed in fullness from his conception comes to “rest on him”.5 Jesus will be the source of the Spirit for all mankind. At his baptism “the heavens were opened”6 – the heavens that Adam’s sin had closed – and the waters were sanctified by the descent of Jesus and the Spirit, a prelude to the new creation.

CCC 607 The desire to embrace his Father’s plan of redeeming love inspired Jesus’ whole life,7 for his redemptive passion was the very reason for his Incarnation. And so he asked, “And what shall I say? ‘Father, save me from this hour’? No, for this purpose I have come to this hour.”8 And again, “Shall I not drink the cup which the Father has given me?”9 From the cross, just before “It is finished”, he said, “I thirst.”10

CCC 696 Fire. While water signifies birth and the fruitfulness of life given in the Holy Spirit, fire symbolizes the transforming energy of the Holy Spirit’s actions. The prayer of the prophet Elijah, who “arose like fire” and whose “word burned like a torch,” brought down fire from heaven on the sacrifice on Mount Carmel.11 This event was a “figure” of the fire of the Holy Spirit, who transforms what he touches. John the Baptist, who goes “before [the Lord] in the spirit and power of Elijah,” proclaims Christ as the one who “will baptize you with the Holy Spirit and with fire.”12 Jesus will say of the Spirit: “I came to cast fire upon the earth; and would that it were already kindled!”13 In the form of tongues “as of fire,” the Holy Spirit rests on the disciples on the morning of Pentecost and fills them with himself14 The spiritual tradition has retained this symbolism of fire as one of the most expressive images of the Holy Spirit’s actions.15 “Do not quench the Spirit.”16

CCC 1225 In his Passover Christ opened to all men the fountain of Baptism. He had already spoken of his Passion, which he was about to suffer in Jerusalem, as a “Baptism” with which he had to be baptized.17 The blood and water that flowed from the pierced side of the crucified Jesus are types of Baptism and the Eucharist, the sacraments of new life.18 From then on, it is possible “to be born of water and the Spirit”19 in order to enter the Kingdom of God.
See where you are baptized, see where Baptism comes from, if not from the cross of Christ, from his death. There is the whole mystery: he died for you. In him you are redeemed, in him you are saved.20

CCC 2804 The first series of petitions carries us toward him, for his own sake: thy name, thy kingdom, thy will! It is characteristic of love to think first of the one whom we love. In none of the three petitions do we mention ourselves; the burning desire, even anguish, of the beloved Son for his Father’s glory seizes us:21 “hallowed be thy name, thy kingdom come, thy will be done. .. ” These three supplications were already answered in the saving sacrifice of Christ, but they are henceforth directed in hope toward their final fulfillment, for God is not yet all in all.22

1 Jn 1:29; cf. Is 53:12.
2 Cf. Mk 10:38; Lk 12:50.
3 Mt 3:15; cf. 26:39.
4 Cf. Lk 3:22; Is 42:1.
5 Jn 1:32-33; cf. Is 11:2.
6 Mt 3:16.
7 Cf Lk 12:50; 22:15; Mt 16:21-23.
8 Jn 12:27.
9 Jn 18:11.
10 Jn 19:30; 19:28.
11 Sir 48:1; cf. 1 Kings 18:38-39.
12 Lk 1:17; 3:16.
13 Lk 12:49.
14 Acts 2:3-4.
15 Cf. St. John of the Cross, The Living Flame of Love, in The Collected Works of St. John of the Cross, tr. K. Kavanaugh, OCD, and O. Rodriguez, OCD (Washington DC: Institute of Carmelite Studies, 1979), 577 ff.
16 1 Thess 5:1.
17 Mk 10:38; cf. Lk 12:50.
18 Cf. Jn 19:34; 1 Jn 5:6-8.
19 Cf. Jn 3:5.
20 St. Ambrose, De sacr. 2, 2, 6: PL 16, 444; cf. Jn 3:5.
21 Cf. Lk 22:14; 12:50.
22 Cf. 1 Cor 15:28.