Heidelberg Catechism · Lord's Day 41
109. Does God in this commandment forbid nothing more than adultery and such gross sins?
Answer
Since our body and soul are both temples of the Holy Spirit, it is God's will that we keep both pure and holy. Therefore he forbids all unchaste acts, gestures, words, thoughts, desires, and whatever may entice us to unchastity.
Scripture references
Question 109 of 129
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