Heidelberg Catechism · Lord's Day 26
69. How does holy baptism signify and seal to you that the one sacrifice of Christ on the cross benefits you?
Answer
In this way: Christ has instituted this outward washing with water and has joined to it this promise, that I am washed with his blood and Spirit from the uncleanness of my soul, that is, from all my sins, as certainly as I am washed outwardly with water, by which the uncleanness of the body is commonly washed away.
Scripture references
Question 69 of 129
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