CIC 553 Jesus entrusted a specific authority to Peter: “I will give you the keys of the kingdom of heaven, and whatever you bind on earth shall be bound in heaven, and whatever you loose on earth shall be loosed in heaven.”1 The “power of the keys” designates authority to govern the house of God, which is the Church. Jesus, the Good Shepherd, confirmed this mandate after his Resurrection: “Feed my sheep.”2 The power to “bind and loose” connotes the authority to absolve sins, to pronounce doctrinal judgements, and to make disciplinary decisions in the Church. Jesus entrusted this authority to the Church through the ministry of the apostles3 and in particular through the ministry of Peter, the only one to whom he specifically entrusted the keys of the kingdom.

CIC 1088 “To accomplish so great a work” – the dispensation or communication of his work of salvation – “Christ is always present in his Church, especially in her liturgical celebrations. He is present in the Sacrifice of the Mass not only in the person of his minister, ‘the same now offering, through the ministry of priests, who formerly offered himself on the cross,’ but especially in the Eucharistic species. By his power he is present in the sacraments so that when anybody baptizes, it is really Christ himself who baptizes. He is present in his word since it is he himself who speaks when the holy Scriptures are read in the Church. Lastly, he is present when the Church prays and sings, for he has promised ‘where two or three are gathered together in my name there am I in the midst of them.”’4

CIC 1373 “Christ Jesus, who died, yes, who was raised from the dead, who is at the right hand of God, who indeed intercedes for us,” is present in many ways to his Church:5 in his word, in his Church’s prayer, “where two or three are gathered in my name,”6 in the poor, the sick, and the imprisoned,7 in the sacraments of which he is the author, in the sacrifice of the Mass, and in the person of the minister. But “he is present. .. most especially in the Eucharistic species.”8

CIC 1444 In imparting to his apostles his own power to forgive sins the Lord also gives them the authority to reconcile sinners with the Church. This ecclesial dimension of their task is expressed most notably in Christ’s solemn words to Simon Peter: “I will give you the keys of the kingdom of heaven, and whatever you bind on earth shall be bound in heaven, and whatever you loose on earth shall be loosed in heaven.”9 “The office of binding and loosing which was given to Peter was also assigned to the college of the apostles united to its head.”10

CIC 2472 The duty of Christians to take part in the life of the Church impels them to act as witnesses of the Gospel and of the obligations that flow from it. This witness is a transmission of the faith in words and deeds. Witness is an act of justice that establishes the truth or makes it known.11
All Christians by the example of their lives and the witness of their word, wherever they live, have an obligation to manifest the new man which they have put on in Baptism and to reveal the power of the Holy Spirit by whom they were strengthened at Confirmation.

1 Mt 16:19.
2 Jn 21:15-17; Cf. 10:11.
3 Cf. Mt 18:18.
4 SC 7; Mt 18:20.
5 Rom 8:34; cf. LG 48.
6 Mt 18:20.
7 Cf. Mt 25:31-46.
8 SC 7.
9 Mt 16:19; cf. Mt 18:18; 28:16-20.
10 LG 22 # 2.
11 Cf. Mt 18:16.