CIC 249 From the beginning, the revealed truth of the Holy Trinity has been at the very root of the Church’s living faith, principally by means of Baptism. It finds its expression in the rule of baptismal faith, formulated in the preaching, catechesis and prayer of the Church. Such formulations are already found in the apostolic writings, such as this salutation taken up in the Eucharistic liturgy: “The grace of the Lord Jesus Christ and the love of God and the fellowship of the Holy Spirit be with you all.”1

CIC 308 The truth that God is at work in all the actions of his creatures is inseparable from faith in God the Creator. God is the first cause who operates in and through secondary causes: “For God is at work in you, both to will and to work for his good pleasure.”2 Far from diminishing the creature’s dignity, this truth enhances it. Drawn from nothingness by God’s power, wisdom and goodness, it can do nothing if it is cut off from its origin, for “without a Creator the creature vanishes.”3 Still less can a creature attain its ultimate end without the help of God’s grace.4

CIC 683 “No one can say ‘Jesus is Lord’ except by the Holy Spirit.”5 “God has sent the Spirit of his Son into our hearts, crying, ‘Abba! Father!”’6 This knowledge of faith is possible only in the Holy Spirit: to be in touch with Christ, we must first have been touched by the Holy Spirit. He comes to meet us and kindles faith in us. By virtue of our Baptism, the first sacrament of the faith, the Holy Spirit in the Church communicates to us, intimately and personally, the life that originates in the Father and is offered to us in the Son.
Baptism gives us the grace of new birth in God the Father, through his Son, in the Holy Spirit. For those who bear God’s Spirit are led to the Word, that is, to the Son, and the Son presents them to the Father, and the Father confers incorruptibility on them. And it is impossible to see God’s Son without the Spirit, and no one can approach the Father without the Son, for the knowledge of the Father is the Son, and the knowledge of God’s Son is obtained through the Holy Spirit.7

CIC 694 Water. The symbolism of water signifies the Holy Spirit’s action in Baptism, since after the invocation of the Holy Spirit it becomes the efficacious sacramental sign of new birth: just as the gestation of our first birth took place in water, so the water of Baptism truly signifies that our birth into the divine life is given to us in the Holy Spirit. As “by one Spirit we were all baptized,” so we are also “made to drink of one Spirit.”8 Thus the Spirit is also personally the living water welling up from Christ crucified9 as its source and welling up in us to eternal life.10

CIC 790 Believers who respond to God’s word and become members of Christ’s Body, become intimately united with him: “In that body the life of Christ is communicated to those who believe, and who, through the sacraments, are united in a hidden and real way to Christ in his Passion and glorification.”11 This is especially true of Baptism, which unites us to Christ’s death and Resurrection, and the Eucharist, by which “really sharing in the body of the Lord,. .. we are taken up into communion with him and with one another.”12

CIC 798 The Holy Spirit is “the principle of every vital and truly saving action in each part of the Body.”13 He works in many ways to build up the whole Body in charity:14 by God’s Word “which is able to build you up”;15 by Baptism, through which he forms Christ’s Body;16 by the sacraments, which give growth and healing to Christ’s members; by “the grace of the apostles, which holds first place among his gifts”;17 by the virtues, which make us act according to what is good; finally, by the many special graces (called “charisms”), by which he makes the faithful “fit and ready to undertake various tasks and offices for the renewal and building up of the Church.”18

CIC 801 It is in this sense that discernment of charisms is always necessary. No charism is exempt from being referred and submitted to the Church’s shepherds. “Their office [is] not indeed to extinguish the Spirit, but to test all things and hold fast to what is good,”19 so that all the diverse and complementary charisms work together “for the common good.”20

CIC 1227 According to the Apostle Paul, the believer enters through Baptism into communion with Christ’s death, is buried with him, and rises with him:
Do you not know that all of us who have been baptized into Christ Jesus were baptized into his death? We were buried therefore with him by baptism into death, so that as Christ was raised from the dead by the glory of the Father, we too might walk in newness of life.21
The baptized have “put on Christ.”22 Through the Holy Spirit, Baptism is a bath that purifies, justifies, and sanctifies.23

CIC 1267 Baptism makes us members of the Body of Christ: “Therefore. .. we are members one of another.”24 Baptism incorporates us into the Church. From the baptismal fonts is born the one People of God of the New Covenant, which transcends all the natural or human limits of nations, cultures, races, and sexes: “For by one Spirit we were all baptized into one body.”25

CIC 1396 The unity of the Mystical Body: the Eucharist makes the Church. Those who receive the Eucharist are united more closely to Christ. Through it Christ unites them to all the faithful in one body – the Church. Communion renews, strengthens, and deepens this incorporation into the Church, already achieved by Baptism. In Baptism we have been called to form but one body.26 The Eucharist fulfills this call: “The cup of blessing which we bless, is it not a participation in the blood of Christ? The bread which we break, is it not a participation in the body of Christ? Because there is one bread, we who are many are one body, for we all partake of the one bread:”27
If you are the body and members of Christ, then it is your sacrament that is placed on the table of the Lord; it is your sacrament that you receive. To that which you are you respond “Amen” (“yes, it is true!”) and by responding to it you assent to it. For you hear the words, “the Body of Christ” and respond “Amen.” Be then a member of the Body of Christ that your Amen may be true.28

CIC 1454 The reception of this sacrament ought to be prepared for by an examination of conscience made in the light of the Word of God. The passages best suited to this can be found in the Ten Commandments, the moral catechesis of the Gospels and the apostolic letters, such as the Sermon on the Mount and the apostolic teachings.29

CIC 1988 Through the power of the Holy Spirit we take part in Christ’s Passion by dying to sin, and in his Resurrection by being born to a new life; we are members of his Body which is the Church, branches grafted onto the vine which is himself:30
[God] gave himself to us through his Spirit. By the participation of the Spirit, we become communicants in the divine nature. .. For this reason, those in whom the Spirit dwells are divinized.31

CIC 2003 Grace is first and foremost the gift of the Spirit who justifies and sanctifies us. But grace also includes the gifts that the Spirit grants us to associate us with his work, to enable us to collaborate in the salvation of others and in the growth of the Body of Christ, the Church. There are sacramental graces, gifts proper to the different sacraments. There are furthermore special graces, also called charisms after the Greek term used by St. Paul and meaning “favor,” “gratuitous gift,” “benefit.”32 Whatever their character – sometimes it is extraordinary, such as the gift of miracles or of tongues – charisms are oriented toward sanctifying grace and are intended for the common good of the Church. They are at the service of charity which builds up the Church.33

CIC 2670 “No one can say ‘Jesus is Lord’ except by the Holy Spirit.”34 Every time we begin to pray to Jesus it is the Holy Spirit who draws us on the way of prayer by his prevenient grace. Since he teaches us to pray by recalling Christ, how could we not pray to the Spirit too? That is why the Church invites us to call upon the Holy Spirit every day, especially at the beginning and the end of every important action.
If the Spirit should not be worshiped, how can he divinize me through Baptism? If he should be worshiped, should he not be the object of adoration?35

1 2 Cor 13:14; cf. 1 Cor 12:4-6; Eph 4:4-6.
2 Phil 2:13; cf. 1 Cor 12:6.
3 GS 36 § 3.
4 Cf. Mt 19:26; Jn 15:5; 14:13
5 1 Cor 12:3.
6 Gal 4:6.
7 St. Irenaeus, Dem. ap. 7: SCh 62, 41-42.
8 1 Cor 12:13.
9 Jn 19:34; 1 Jn 5:8.
10 Cf. Jn 4:10-14; 738; Ex 17:1-6; Isa 55:1; Zech 14:8; 1 Cor 10:4; Rev 21:6; 22:17.
11 LG 7.
12 LG 7; cf. Rom 6:4-5; 1 Cor 12:13.
13 Pius XII, encyclical, Mystici Corporis: DS 3808.
14 Cf. Eph 4:16.
15 Acts 20:32.
16 Cf. 1 Cor 12:13.
17 LG 7 # 2.
18 LG 12 # 2; cf. AA 3.
19 LG 12; cf. 30; 1 Thess 5:12, 19-21; John Paul II, Christifideles Laici, 24.
20 1 Cor 12:7.
21 Rom 6:3-4; cf. Col 2:12.
22 Gal 3:27.
23 CE 1 Cor 6:11; 12:13.
24 Eph 4:25.
25 1 Cor 12:13.
26 Cf. 1 Cor 12:13.
27 1 Cor 10:16-17.
28 St. Augustine, Sermo 272: PL 38, 1247.
29 Cf. Mt 5-7; Rom 12-15; 1 Cor 12-13; Gal 5; Eph 4-6; etc.
30 Cf. 1 Cor 12; Jn 15:1 4.
31 St. Athanasius, Ep. Serap. 1, 24: PG 26, 585 and 588.
32 Cf. LG 12.
33 Cf. 1 Cor 12.
34 1 Cor 12:3.
35 St. Gregory of Nazianzus, Oratio, 31, 28: PG 36, 165.