CIC 151 For a Christian, believing in God cannot be separated from believing in the One he sent, his “beloved Son”, in whom the Father is “well pleased”; God tells us to listen to him.1 The Lord himself said to his disciples: “Believe in God, believe also in me.”2 We can believe in Jesus Christ because he is himself God, the Word made flesh: “No one has ever seen God; the only Son, who is in the bosom of the Father, he has made him known.”3 Because he “has seen the Father”, Jesus Christ is the only one who knows him and can reveal him.4

CIC 259 Being a work at once common and personal, the whole divine economy makes known both what is proper to the divine persons, and their one divine nature. Hence the whole Christian life is a communion with each of the divine persons, without in any way separating them. Everyone who glorifies the Father does so through the Son in the Holy Spirit; everyone who follows Christ does so because the Father draws him and the Spirit moves him.5

CIC 591 Jesus asked the religious authorities of Jerusalem to believe in him because of the Father’s works which he accomplished.6 But such an act of faith must go through a mysterious death to self, for a new “birth from above” under the influence of divine grace.7 Such a demand for conversion in the face of so surprising a fulfillment of the promises8 allows one to understand the Sanhedrin’s tragic misunderstanding of Jesus: they judged that he deserved the death sentence as a blasphemer.9 The members of the Sanhedrin were thus acting at the same time out of “ignorance” and the “hardness” of their “unbelief”.10

CIC 728 Jesus does not reveal the Holy Spirit fully, until he himself has been glorified through his Death and Resurrection. Nevertheless, little by little he alludes to him even in his teaching of the multitudes, as when he reveals that his own flesh will be food for the life of the world.11 He also alludes to the Spirit in speaking to Nicodemus,12 to the Samaritan woman,13 and to those who take part in the feast of Tabernacles.14 To his disciples he speaks openly of the Spirit in connection with prayer15 and with the witness they will have to bear.16

CIC 1001 When? Definitively “at the last day,” “at the end of the world.”17 Indeed, the resurrection of the dead is closely associated with Christ’s Parousia:
For the Lord himself will descend from heaven, with a cry of command, with the archangel’s call, and with the sound of the trumpet of God. And the dead in Christ will rise first.18

CIC 1355 In the communion, preceded by the Lord’s prayer and the breaking of the bread, the faithful receive “the bread of heaven” and “the cup of salvation,” the body and blood of Christ who offered himself “for the life of the world”:19
Because this bread and wine have been made Eucharist (“eucharisted,” according to an ancient expression), “we call this food Eucharist, and no one may take part in it unless he believes that what we teach is true, has received baptism for the forgiveness of sins and new birth, and lives in keeping with what Christ taught.”20

CIC 1428 Christ’s call to conversion continues to resound in the lives of Christians. This second conversion is an uninterrupted task for the whole Church who, “clasping sinners to her bosom, [is] at once holy and always in need of purification, [and] follows constantly the path of penance and renewal.”21 This endeavor of conversion is not just a human work. It is the movement of a “contrite heart,” drawn and moved by grace to respond to the merciful love of God who loved us first.22

CIC 2835 This petition, with the responsibility it involves, also applies to another hunger from which men are perishing: “Man does not live by bread alone, but. .. by every word that proceeds from the mouth of God,”23 that is, by the Word he speaks and the Spirit he breathes forth. Christians must make every effort “to proclaim the good news to the poor.” There is a famine on earth, “not a famine of bread, nor a thirst for water, but of hearing the words of the LORD.”24 For this reason the specifically Christian sense of this fourth petition concerns the Bread of Life: The Word of God accepted in faith, the Body of Christ received in the Eucharist.25

CIC 2837 “Daily” (epiousios) occurs nowhere else in the New Testament. Taken in a temporal sense, this word is a pedagogical repetition of “this day,”26 to confirm us in trust “without reservation.” Taken in the qualitative sense, it signifies what is necessary for life, and more broadly every good thing sufficient for subsistence.27 Taken literally (epi-ousios: “super-essential”), it refers directly to the Bread of Life, the Body of Christ, the “medicine of immortality,” without which we have no life within us.28 Finally in this connection, its heavenly meaning is evident: “this day” is the Day of the Lord, the day of the feast of the kingdom, anticipated in the Eucharist that is already the foretaste of the kingdom to come. For this reason it is fitting for the Eucharistic liturgy to be celebrated each day.
The Eucharist is our daily bread. The power belonging to this divine food makes it a bond of union. Its effect is then understood as unity, so that, gathered into his Body and made members of him, we may become what we receive. .. This also is our daily bread: the readings you hear each day in church and the hymns you hear and sing. All these are necessities for our pilgrimage.29
The Father in heaven urges us, as children of heaven, to ask for the bread of heaven. [Christ] himself is the bread who, sown in the Virgin, raised up in the flesh, kneaded in the Passion, baked in the oven of the tomb, reserved in churches, brought to altars, furnishes the faithful each day with food from heaven.30

1 Mk 1:11; cf. 9:7.
2 Jn 14:1.
3 Jn 1:18.
4 Jn 6:46; cf. Mt 11:27.
5 Cf. Jn 6:44; Rom 8:14.
6 Jn 10:36-38.
7 Cf. Jn 3:7; 6:44.
8 Cf. Is 53:1.
9 Cf. Mk 3:6; Mt 26:64-66.
10 Cf. Lk 23 34; Acts 3: 17-18; Mk 3:5; Rom 11:25, 20.
11 Cf. Jn 6:27, 51, 62-63.
12 Cf. Jn 3:5-8.
13 Cf. Jn 4:10, 14, 23-24.
14 Cf. Jn 7:37-39.
15 Cf. Lk 11:13.
16 Cf. Mt 10:19-20.
17 Jn 6: 39-40,44,54; 11:24; LG 48 § 3.
18 1 Thess 4:16.
19 Jn 6:51.
20 St. Justin, Apol. 1, 66,1-2: PG 6, 428.
21 LG 8 # 3.
22 Ps 51:17; cf. Jn 6:44; 12:32; 1 Jn 4:10.
23 Deut 8:3; Mt 4:4.
24 Am 8:11.
25 Cf. Jn 6:26-58.
26 Cf. Ex 16:19-21.
27 Cf. 1 Tim 6:8.
28 St. Ignatius Of Antioch, Ad Eph. 20, 2 PG 5, 661; Jn 6:53-56.
29 St. Augustine, Sermo 57, 7: PL 38, 389.
30 St. Peter Chrysologus, Sermo 67 PL 52, 392; Cf. Jn 6:51.