A Summary on the Laity of Ad Gentes
AG 11
These excerpts are just the beginning. To truly soak in these teachings, I encourage you to explore the original document.
The Church must be present in these groups through her children, who dwell among them or who are sent to them. For all Christians, wherever they live, are bound to show forth, by the example of their lives and by the witness of the word, that new man put on at baptism and that power of the Holy Spirit by which they have been strengthened at Confirmation. Thus other men, observing their good works, can glorify the Father (cf. Matt. ES:16) and can perceive more fully the real meaning of human life and the universal bond of the community of mankind.
In order that they may be able to bear more fruitful witness to Christ, let them be joined to those men by esteem and love; let them acknowledge themselves to be members of the group of men among whom they live; let them share in cultural and social life by the various. undertakings and enterprises of human living; let them be familiar with their national and religious traditions; let them gladly and reverently lay bare the seeds of the Word which lie hidden among their fellows.
At the same time, however, let them look to the: profound changes which are taking place among nations, and let them exert themselves to keep modern man, intent as he is on the science and technology of today's world from becoming a stranger to things divine; rather, let them awaken in him a yearning for that truth and charity which God has revealed. Even as Christ Himself searched the hearts of men, and led them to divine light, so also His disciples, profoundly penetrated by the Spirit of Christ, should show the people among whom they live, and should converse with them, that they themselves may learn by sincere and patient dialogue what treasures a generous God has distributed among the nations of the earth. But at the same time, let them try to furbish these treasures, set them free, and bring them under the dominion of God their Saviour.
AG 15
The Holy Spirit, who calls all men to Christ by the seeds of the Lord and by the preaching of the Gospel, stirs up in their: hearts a submission to the faith Who in the womb of the baptismal font, He begets to a new life those who believe in Christ, He gathers them into the one People of God which is "a chosen race, a royal priesthood, a holy nation, a purchased people" (1 Peter 2:9).(8)
Therefore, let the missionaries, God's coworkers, ( cf. 1 Cor. 3:9), raise up congregations of the faithful such that, walking worthy of the vocation to which they have been called (cf. Eph. 4:1), they may exercise the priestly, prophetic, and royal office which God has entrusted to them. In this way, the Christian community will be a sign of God's presence in the world: for by reason of the eucharistic sacrifice, this community is ceaselessly on the way with Christ to the Father;(9) carefully nourished on the word of God(10) it bears witness to Christ;(11) and finally, it walks in charity and is fervent with the apostolic spirit.(12)
The Christian community should from the very start be so formed that it call provide nor its necessities insofar as this is possible.
This congregation of the faithful, endowed with the riches of its own nation's culture, should be deeply rooted in the people. Let families flourish which are imbued with the spirit of the Gospel(13) and let them be assisted by good schools; let associations and groups be organized by means of which the lay apostolate will be able to permeate the whole of society with the spirit of the Gospel. Lastly, let charity shine out between Catholics of different rites.(14)
The ecumenical spirit should be nurtured in the neophytes, who should take into account that the brethren who believe in Christ are Christ's disciples, reborn in baptism, sharers with the People of God in very many good things.
Insofar as religious conditions allow, ecumenical activity - should be furthered in such a way that, excluding any appearance of indifference or confusion on the one hand, or of unhealthy rivalry on the other, Catholics should cooperate in a brotherly spirit with their separated brethren, among to the norms of the Decree on Ecumenism, making before the nations a common profession of faith, insofar as their beliefs are common, in God and in Jesus Christ, and cooperating in social and in technical projects as well as in cultural and religious ones. Let them cooperate especially for the sake of Christ, their common Lord: let His Name be the bond that unites them! This cooperation should be undertaken not only among private persons, but also, subject to approval by the local Ordinary, among churches or ecclesial communities and their works.
The Christian faithful gathered together out of all nations into the Church "are not marked off from the rest of men by their government, nor by their language, nor by their political institutions,"(15) and so they should live for God and Christ in a respectable way of their own national life. As good citizens, they should be true and effective patriots, all together avoiding racial prejudice and hypernationalism, and should foster a universal love for man.
To obtain all these things, the most important and therefore worthy of special attention are the Christian laity: namely, those who have been incorporated into Christ and live in the world. For it is up to them, imbued with the spirit of Christ, to be a leaven working on the temporal order from within, to dispose it always in accordance with Christ.(16)
But it is not enough that the Christian people be present and be organized in a given nation, nor is it enough to carry out an apostolate by way of example. They are organized for this purpose, they are present for this, to announce Christ to their non - Christian fellow - citizens by word and example, and to aid them toward the full reception of Christ.
AG 21
The church has not been really founded, and is not yet fully alive, nor is it a perfect sign of Christ among men, unless there is a laity worthy of the name working along with the hierarchy. For the Gospel cannot be deeply grounded in the abilities, life and work of any people without the active presence of laymen. Therefore, even at the very founding of a Church, great attention is to be paid to establishing a mature, Christian laity.
For the lay faithful fully belong at one and the same time both to the People of God and to civil society: they belong to the nation in which they were born; they have begun to share in its cultural treasures by means of their education; they are joined to its life by manifold social ties; they are cooperating in its progress by their efforts, each in his own profession; they feel its problems to be their very own, and they are trying to solve them. They also belong to Christ, because they were regenerated in the Church by faith and by baptism, so that they are Christ's in newness of life and work (cf. 1 Cor. 15:23), in order that in Christ, all things may be made subject to God, and finally God will be all in all (cf. Cor. 15:28).
Their main duty, whether they are men or women, is the witness which they are bound to bear to Christ by their life and works in the home, in their social milieu, and in their own professional circle. In them, there must appear the new man created according to God in justice and true holiness (cf. Eph. 4:24). But they must give expression to this newness of life in the social and cultural framework of their own homeland, according to their own national traditions. They must be acquainted with this culture; they must heal it and preserve it; they must develop it in accordance with modern conditions, and finally perfect it in Christ, so that the Faith of Christ and the life of the Church are no longer foreign to the society in which they live, but begin to permeate and to transform it. Let them be one with their fellow countrymen in sincere charity, so that there appears in their way of life a new bond of unity and of universal solidarity, which is drawn from the mystery of Christ. Let them also spread the Faith of Christ among those with whom they live or have professional connections - an obligation which is all the more urgent, because very many men can hear of Christ and of the Gospel only by means of the laity who are their neighbors. In fact, wherever possible, the laity should be prepared, in more immediate cooperation with the hierarchy, to fulfill a special mission of proclaiming the Gospel and communicating Christian teachings, so that they may add vigor to the nascent Church.
Let the clergy highly esteem the arduous apostolate of the laity. Let them train the laity to become conscious of the responsibility which they as members of Christ have for all men; let them instruct them deeply in the mystery of Christ, introduce them to practical methods, and be at their side in difficulties, according to the tenor of the Constitution Lumen Gentium and the Decree Apostolicam Actuositatem.
While pastors and laymen, then, retain each their own state of life and their own responsibilities, let the whole young church render one firm and vital witness to Christ, and become a shining beacon of the salvation which comes to us in Christ.
Second Vatican Council, Decree Ad Gentes on the Mission Activity of the Church, 1965, 7 December 1965.
Official text: Vatican.va