If you do not have one, please obtain a copy of the catechism, as there are far too many explanations in it to post here. Some amazing reading in there. Here is a page on the Sacraments from the online catechism. The complete online catechism is posted here.
God’s grace is supernatural. Man is natural. And yet grace brings man up to supernatural virtue in hope, faith, and love.
This is the mystery of grace, and one that is far beyond and above the light of human intellect.
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