CATECHISM OF THE CATHOLIC CHURCH
SECOND EDITION

Paragraphs 897–901

897 "The term 'laity' is here understood to mean all the faithful except those in Holy Orders and those who belong to a religious state approved by the Church. That is, the faithful, who by Baptism are incorporated into Christ and integrated into the People of God, are made sharers in their particular way in the priestly, prophetic, and kingly office of Christ, and have their own part to play in the mission of the whole Christian people in the Church and in the World."
898 "By reason of their special vocation it belongs to the laity to seek the kingdom of God by engaging in temporal affairs and directing them according to God's will. . . . It pertains to them in a special way so to illuminate and order all temporal things with which they are closely associated that these may always be effected and grow according to Christ and maybe to the glory of the Creator and Redeemer."
899 The initiative of lay Christians is necessary especially when the matter involves discovering or inventing the means for permeating social, political, and economic realities with the demands of Christian doctrine and life. This initiative is a normal element of the life of the Church:

Lay believers are in the front line of Church life; for them the Church is the animating principle of human society. Therefore, they in particular ought to have an ever-clearer consciousness not only of belonging to the Church, but of being the Church, that is to say, the community of the faithful on earth under the leadership of the Pope, the common Head, and of the bishops in communion with him. They are the Church.

900 Since, like all the faithful, lay Christians are entrusted by God with the apostolate by virtue of their Baptism and Confirmation, they have the right and duty, individually or grouped in associations, to work so that the divine message of salvation may be known and accepted by all men throughout the earth. This duty is the more pressing when it is only through them that men can hear the Gospel and know Christ. Their activity in ecclesial communities is so necessary that, for the most part, the apostolate of the pastors cannot be fully effective without it.
901 "Hence the laity, dedicated as they are to Christ and anointed by the Holy Spirit, are marvelously called and prepared so that even richer fruits of the Spirit may be produced in them. For all their works, prayers, and apostolic undertakings, family and married life, daily work, relaxation of mind and body, if they are accomplished in the Spirit - indeed even the hardships of life if patiently born - all these become spiritual sacrifices acceptable to God through Jesus Christ. In the celebration of the Eucharist these may most fittingly be offered to the Father along with the body of the Lord. And so, worshipping everywhere by their holy actions, the laity consecrate the world itself to God, everywhere offering worship by the holiness of their lives."