19 The work of planting the Church in a given human community reaches a certain goal when the congregation of the faithful already rooted in social life and somewhat conformed to the local culture, enjoys a certain firmness and stability. That is to say, it is already equipped with its own supple (perhaps still insufficient) of local priests, Religious, and lay men, and is endowed with these institutions and ministries which are necessary for leading and expanding the life of the people of God under the guidance of their own bishop. In such new churches, the life of the People of God must mature in all those fields of Christian life which are to be reformed by the norms of this council. The congregations of the faithful become daily more aware of their status as communities of faith, liturgy, and love. The laity strive by their civic and apostolic activity to set up a public order based on justice and love. The means of social communication are put to wise use at the opportune time. By a truly Christian life, families become seedbeds of the lay apostolate and of vocations to the priesthood and the Religious life. Finally, the Faith is taught by an adequate catechesis; it is celebrated in a liturgy in harmony with the genius of the people, and by suitable canonical legislation, it is introduced into upright institutions and local customs. The bishops, in turn, each one together with his own college of priests, being more and more imbued with the mind of Christ and of the Church, feel and live along with the universal Church. Let the young church keep up an intimate communion with the whole Church, whose tradition they should link to their own culture, in order to increase, by a certain mutual exchange of forces, the life of the Mystical Body. Hence, stress should be laid on those theological, psychological, and human elements which can contribute to fostering this sense of communion with the universal Church. But these churches, very often located in the poorer portions of the globe, are mostly suffering from a very serious lack of priests and of material support. Therefore, they are badly in need of the continued missionary activity of the whole Church to furnish them with those subsidies which serve for the growth of the local Church, and above all for the maturity of Christian life. This mission action should also furnish help to those churches, founded long since, which are in a certain state of regression or weakness. Yet these churches should launch a common pastoral effort and suitable works to increase the number of vocations to the diocesan clergy and to religious institutes, to discern them more readily, and to train them more efficiently, so that little by little these churches may be able to provide for themselves and to bring aid to others.
Source: Ad Gentes (Vatican.va)