Question: What is a sacrament?
Answer: A sacrament is a sign of the sacred. Sacraments are visible signs that tell us what Christ does and these signs are used by Christ to convey his grace to the members of his Body, the Church. The Catechism of the Catholic Church has a beautiful description of what sacraments are:
Seated at the right hand of the Father and pouring out the Holy Spirit on his Body which is the Church, Christ now acts through the sacraments he instituted to communicate his grace. The sacraments are perceptible signs (words and actions) accessible to our human nature. By the action of Christ and the power of the Holy Spirit they make present efficaciously the grace that they signify. (1084)
The first thing to notice is that it is Christ, not the priest, who acts in the sacraments. The Church performs the ritual (baptising, confirming, anointing) and through the ritual Christ conveys his power. So the Churchs sacraments are the means by which Christ communicates himself to us through signs and rituals.
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