Catechism of the Catholic Church
c and e. Para. 546: Jesus' invitation to enter his kingdom comes in the form of parables, a characteristic feature of his teaching (Cf. Mk 4:33-34). Through his parables he invites people to the feast of the kingdom, but he also asks for a radical choice: to gain the kingdom, one must give everything (Cf. Mt 13:44-45; 22:1-14). Words are not enough; deeds are required (Cf. Mt 21: 28-32). The parables are like mirrors for man: will he be hard soil or good earth for the word? (Cf. Mt 13:3-9) What use has he made of the talents he has received? (Cf. Mt 25: 14-30).
Para. 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" (Mt 16:19). 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" (Jn 21:15-17; cf. 10:11). The power to "bind and loose" connotes the authority to absolve sins, to pronounce doctrinal judgments, and to make disciplinary decisions in the Church. Jesus entrusted this authority to the Church through the ministry of the apostles (Cf. Mt 18:18) and in particular through the ministry of Peter, the only one to whom he specifically entrusted the keys of the kingdom.
Para. 567: The Kingdom of heaven was inaugurated on earth by Christ. "This kingdom shone out before men in the word, in the works, and in the presence of Christ" (LG 5). The Church is the seed and beginning of this kingdom. Her keys are entrusted to Peter.
Para. 547: Jesus accompanies his words with many "mighty works and wonders and signs," which manifest that the kingdom is present in him and attest that he was the promised Messiah (Acts 2:22; cf. Lk 7:18-23).