Jesus instituted the sacraments to (1) sanctify mankind, (2) build up the Church, His Mystical Body, (3) render worship to God, and (4) instruct.
1. Jesus instituted the sacraments to sanctify mankind.
God uses the sacraments as the ordinary channels to impart His grace; therefore, they are necessary to keep and nourish the life of grace in our souls. St. John reminds us that Jesus gives us His grace in order to sanctify us: “And from his fullness have we all received, grace upon grace. For the law was given through Moses; grace and truth came through Jesus Christ” (John 1:16–17).
2. Jesus instituted the sacraments to build up the Church, His Mystical Body.
Each of the sacraments has an indispensable role in the life of the Church, that is, the Mystical Body of Christ. Among them, Baptism, Confirmation, Marriage, and Holy Orders confer a distinct office within the Church.
Through Baptism we become children of God and members of Christ’s Mystical Body, the Church. The baptized are consecrated to be a holy priesthood, sharing in Christ’s divine Priesthood. Confirmation makes us mature and responsible Christians and increases our participation in Christ’s priesthood.
Holy Orders confers the actual power of the ministerial priesthood and provides for the continuation of the Church. In the Sacrament of Marriage, a man and woman become one; it provides for the growth of the Body of Christ by conferring the vocation of parenthood and by guaranteeing the graces which enable parents to guide the new members of Christ.
The Anointing of the Sick prepares us for entrance into the ranks of the Church Triumphant in Heaven. The Sacrament of Penance grants us pardon for our sins and strengthens us to resist temptation. The Holy Eucharist nourishes our souls and gives us an increase of the power to love God and our neighbor.
3. Jesus instituted the sacraments to render worship to God.
Christ continually offers Himself to His Heavenly Father through the Eucharist, by means of the ministry of His priests in the Holy Sacrifice of the Mass. This is the supreme act of worship which can be given to God, because it is offered by the God-man in the spirit in which He offered Himself on the Cross for our redemption. All of us, members of Christ’s Mystical Body, can participate in this oblation, or offering, and thereby give worthy adoration, thanksgiving, and atonement to God.
4. Jesus instituted the sacraments to instruct.
Signs are actions which convey an idea; words are signs which convey an idea. In the sacraments both the words and the actions make up the sacred sign.