In ancient Roman days, a "sacramentum" was a solemn oath which a man took according to law. Literally, the word meant "a sacred act," for an oath was considered to be a sacred thing, as the poet says, "Man's word is God in man."
The early Christians adopted this word to apply to certain sacred acts of the Christian religion, acts which were external signs of some deep spiritual significance. The external acts to which the word "sacrament" was applied were those which Christ Himself had instituted for the sacred purpose of applying to men's souls the grace of His redemption.
The sacraments are seven--
Baptism, Confirmation, Holy Communion, Penance or Confession, Matrimony, Holy Orders, and the Anointing of the Sick. All of them consist of some material fact--water, oil, bread, wine--and some external act: pouring, anointing, laying on of hands, uttering words, and all of them by these means symbolize the application of Christ's redemptive grace to men's souls and actually confer this grace.
Why did Christ institute sacraments? Why, indeed, did Christ redeem us by His life, suffering, death and resurrection, when a simple act of the divine will could have accomplished the same result? Sufficient for us to know that He did this--the fullness of the reason for it is hidden within the divine mind.
Yet we can see, at least partially, why the redemption was effected as it was. It was fitting that God should deal with His creature according to the manner in which He had created him. It was fitting that He should show His love for man by sending His own Son to become man. It was fitting that the human nature which He created and called good should have been sanctified by the presence of the divine Christ, that the human flesh which He assumed should have been redeemed from within, so to speak, by this presence.
And similarly, we can see why the redemption, once won through Christ's life and death would be made available to men through the sacraments of the Church.
Such is God's way of dealing with the free human beings whom He has created. He has permitted man to share in all His works. He does not create men individually from nothing, but brings men into existence through the cooperation of others of their kind, through human parents. He does not govern His universe directly, but through the agency of men. He has not made salvation something automatic, depriving man of his freedom. He has established a Church in which the grace of salvation will be distributed by man to man.
God's Plan of Salvation
By this means He has renewed and blessed once more the creation which "was made subject to vanity not by its own choice but by the will of him who made it subject" (Rom 8:20). Through the sin of man all creation was thrown into disorder, pitted against itself. In the sacramental order which Christ established, even the inanimate things of creation are "delivered from slavery to corruption to enjoy the freedom that comes with the glory of the children of God" (Rom 8:21). Water and wine, oil and bread, become part of God's great plan of salvation, assisting in their own way the glory of the children of God.
This plan of salvation follows the example set by our Lord. Christ taught by signs--signs of fact and signs of word. His most sublime teachings were cloaked in parables: signs in words. He worked cures by means of signs. Remember, for example, His cure of the man blind from birth. He could have simply willed that the man see. But instead, "he spat on the ground, and by means of the spittle made a lump of clay, and then spread the clay over his eyes, and said to him: `Go, and wash' ... So he went, and washed, and came back able to see" (John 9:6f.). It is not surprising that Christ should have decided to distribute salvation to man down through the ages by means of the signs which we call sacraments.
Each of the sacraments has some visible sign. This is what is called the "matter"--that is, a thing, such as water in Baptism and oil in the Anointing of the Sick; and in the "form", that is, certain words. In Baptism, as is well known, the words are: "I baptize you in the name of the Father, and of the Son, and of the Holy Spirit."
In each case, therefore, the matter and form "signify" the spiritual good that is being worked in the soul of the recipient--that is why they are called signs. Water suggests washing, oil suggests healing, and the words of the minister of the sacrament determine what kind of washing and healing is being done.
If the sacraments were merely of human origin, they could be nothing more than signs of our hope or our prayers. We could not assure ourselves that we were really washing a soul clean of sin in Baptism, for example, as only the divine power can do this. But because the sacraments have been instituted by Christ for the express purpose of doing what they symbolize, we know that they are more than mere signs. What they signify, they actually accomplish. Baptism does cleanse a soul from sin. Confirmation does strengthen the life of the spirit and bring it to spiritual adulthood. Communion is not merely a sign of Christ's body and blood, it IS these things.
Means to Grace
This does not mean, of course, that the sacraments are magical or automatic. They must be administered by someone qualified by Christ to do so who is really intending to administer one of Christ's sacraments. The recipient must be prepared and capable of receiving the sacrament. If the sacrament is to him only an idle gesture, it will do him no good. God does not require us to receive the sacraments; to each is given the free will to choose, but in rejecting the sacraments, we reject the means to grace which God freely offers us.
The sacraments were meant to be administered by Christians to Christians in the Church. They are the chief title which the Church has to her claim to be "holy." The Christian living the life of Christ in the Church has these means constantly at his disposal to preserve, to restore, to increase the kind of life which Christ has made it possible for him to live.
Before His ascension into heaven, our Lord gave His Apostles the great commission to baptize. This is, in a sense, the Church's charter of sanctification. "Absolute authority in heaven and on earth has been conferred upon me," He said. "Go, therefore, and initiate all nations in discipleship: baptize them in the name of the Father and of the Son and of the Holy Spirit, and teach them to observe all the commandments I have given you" (Matt. 28:18f.).