The purpose of the sacraments is to make people holy, to build up the Body of Christ, and finally, to give worship to God; but being signs they also have a teaching function. They not only presuppose faith, but by words and objects they also nourish, strengthen, and express it; that is why they are called “sacraments of faith.” They do indeed impart grace, but, in addition, the very act of celebrating them disposes the faithful most effectively to receive this grace in a fruitful manner, to worship God rightly, and to practice charity.

Constitution on the Sacred Liturgy, no. 59