Heidelberg Catechism · Lord's Day 36
99. What is required in the third commandment?
Answer
That we must not by cursing or perjury or unnecessary oaths profane or abuse the name of God, nor share in such horrible sins by being silent bystanders. In a word, that we use the holy name of God only with reverence and awe, so that we may rightly confess him, call upon him, and praise him in all our words and works.
Scripture references
Question 99 of 129
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