HistoryThe history of human salvation is the history of the way God came to men. The first step on this way was the bridging of the gulf separating God and man in the person of the one Mediator Jesus Christ and by his work of redemption. By means of his Church Christ makes his grace available to all. Only in this application of redemption to mankind is the redemptive action of Christ completed. The doctrine of the sacraments is the doctrine of the second part of God's way of salvation to us. It deals with the holy signs which Christ instituted as the vehicles of his grace.
The great mystery of the union in Christ of a human nature with the second Person of the Godhead is that the human actions and sufferings of Christ are divine actions and sufferings. The sacraments are a living continuation of this mystery. There are earthly, external signs here which, of themselves, could never acquire any supernatural significance, but the signs of the sacraments have been made by Christ into vehicles of his grace. They effect in men the grace for which Christ made them the sign.
Sacramentals are instituted by the Church and are effective by virtue of the Church's intercession. Institution and alteration of them is reserved to the Holy See.
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The Seven Sacraments of the Catholic Church
The Church Thus Teaches: There are seven sacraments. They were instituted by Christ and given to the Church to administer. They are necessary for salvation. The sacraments are the vehicles of grace which they convey. They are validly administered by the carrying out of the sign with the proper intention. Not all are equally qualified to administer all the sacraments. The validity of the sacrament is independent of the worthiness of the minister. Three sacraments imprint an indelible character.