1. As we said in the previous catechesis, it is not possible to understand the origin of the Church without taking into account all that Jesus preached and worked (cf. Acts 1:1). And it was precisely on this subject that he addressed his disciples and left us all a fundamental teaching in the parables about the Kingdom of God. Among these, of particular importance are those that enunciate and make us discover the character of historical and spiritual development that is proper to the Church according to the plan of its Founder himself.

2. Jesus says: "The Kingdom of God is like a man who sows a seed in the earth: sleep or wake, night or day, the seed germinates and grows; how, he himself does not know. For the earth produces spontaneously, first the stalk, then the ear, then the full grain in the ear. When the fruit is ready, immediately you put your hand to the sickle, because the harvest has come" (Mk 4:26-29). So the Kingdom of God grows here on earth, in human history, by virtue of an initial sowing, that is, of a foundation, which comes from God, and of a mysterious working of God himself, which continues to cultivate the Church down the centuries. In God's work for the Kingdom, the sickle of sacrifice is also present: the development of the Kingdom is not achieved without suffering. This is the meaning of the parable in Mark's Gospel.

3. We also find the same concept in other parables, especially those gathered in Matthew's text (Mt 13:3-50).

"The kingdom of heaven," we read in this Gospel, "can be compared to a mustard seed, which a man takes and sows in his field. It is the smallest of all seeds, but when it has grown, it is larger than all the other seeds and becomes a tree, so that the birds of heaven nestle among its branches" (Mt 13:31). This is the growth of the kingdom in the "extensive" sense.

Another parable, on the other hand, shows its growth in an "intensive" or qualitative sense, comparing it to the yeast, which a woman took and mixed with three measures of flour so that it all fermented" (Mt 13:32).

4. In the parable of the sower and the sowing, the growth of the Kingdom of God certainly appears as the fruit of the work of the sower, but it is in relation to the soil and the climatic conditions that the sowing produces harvest: "where the hundred, where the sixty, where the thirty" (Mt 13:8). The soil means the inner readiness of men. Therefore, according to Jesus, the growth of the Kingdom of God is also conditioned by man. Human free will is responsible for this growth. This is why Jesus recommends to all to pray: "Thy kingdom come" (cf. Mt 6:10; Lk 11:2): it is one of the first questions of the Pater noster.

5. One of the parables narrated by Jesus on the growth of the Kingdom of God on earth makes us discover very realistically the character of struggle that the kingdom entails, due to the presence and action of an "enemy", who "sows the weeds (or grass) in the midst of the wheat". Jesus says that when "the harvest flourished and bore fruit, behold, the weeds also appeared". The servants of the master of the field would like to pluck it, but the master does not allow them to do so, "lest . . . uproot the wheat also. Let the one and the other grow together until the harvest, and at the time of the harvest I will say to the reapers, 'Harvest the darnel first and bind it in bundles to burn it; but the wheat put it in my barn' (Mt 13:24-30). This parable explains the coexistence and often the intertwining of good and evil in the world, in our lives, in the very history of the Church. Jesus teaches us to see things with Christian realism and to treat every problem with clarity of principles, but also with prudence and patience. This presupposes a transcendent vision of history, in which we know that everything belongs to God and every final outcome is the work of his Providence. However, the final fate - with an eschatological dimension - of the good and the bad is not hidden: it is symbolised by the harvesting of the wheat in the storehouse and the burning of the tares.

6. The explanation of the parable about sowing is given by Jesus himself, at the disciples' request (cf. Mt 13:36-43). In his words emerges both the temporal and eschatological dimension of the Kingdom of God.

He says to his own: "To you has been confided the mystery of the Kingdom of God" (Mk 4:11). About this mystery he instructs them and, at the same time, by his word and his work he "prepares for them a kingdom, just as the Father (Son) has prepared it for him" (cf. Lk 22:29). This preparation is continued even after his resurrection: we read in the Acts of the Apostles that "he appeared to them for forty days and spoke to them of the Kingdom of God" (cf. Acts 1:3) until the day when "he was taken up into heaven and sat down at the right hand of God (Mk 16:19). These were the last instructions and dispositions to the Apostles on what they had to do after the Ascension and Pentecost to give a concrete start to the Kingdom of God in the origin of the Church.

7. The words addressed to Peter at Caesarea Philippi are also part of the preaching about the kingdom. In fact, he says to him: "To you I will give the keys of the kingdom of heaven" (Mt 16:19), immediately after having called him a stone, on which he will build his Church, which will be invincible against "the gates of hell" (cf. Mt 16:18). It is a promise expressed then with the verb in the future tense: "I will build", because the definitive foundation of the Kingdom of God in this world was yet to be accomplished through the sacrifice of the Cross and the victory of the Resurrection. After that, Peter, with the other Apostles, will have the living consciousness of their calling to "proclaim the wonderful works of him who called them out of darkness into his admirable light" (cf. 1 Pet 2:9). At the same time, all will also have an awareness of the truth that emerges from the parable of the sower, namely that "neither he who plants nor he who waters is anything, but God who makes it grow", as St Paul wrote (1 Cor 3:7).

8. The author of the Book of Revelation expresses this same kingdom consciousness when he relates the song addressed to the Lamb: "You were slain and redeemed for God with your blood men of every tribe and tongue and people and nation, and you made them for our God a kingdom of priests" (Rev 5:9-10). The Apostle Peter specifies that they were constituted as such "to offer sacrifices acceptable to God through Jesus Christ" (cf. 1 Pet 2:5). These are all expressions of the truths learnt from Jesus who, in the parables about the sower and the sowing of the seed, about the growth of the wheat and the weeds, about the mustard seed that is sown and then becomes a fairly large plant, spoke of a Kingdom of God that, under the action of the Spirit, grows in souls thanks to the life force resulting from his death and resurrection: a kingdom that grows until the time foreseen by God himself.

9. "Then shall be the end," announces St Paul, "when he (Christ) shall deliver up the kingdom to God the Father, having reduced all principality and power and might to nothing" (1 Cor 15:24). For when "all things have been subdued to him, he also, the Son, will be subdued to him who has subdued all things to him, that God may be all in all" (1 Cor 15:28).

In an admirable eschatological perspective of the Kingdom of God is inscribed the existence of the Church from the beginning to the end, and its history unfolds from the first to the last day.

[Pope John Paul II, General Audience 25 September 1991]