Heidelberg Catechism · Lord's Day 36
100. Is the profaning of God's name by swearing and cursing so serious a sin that God is angry also with those who do not do all they can to help prevent and forbid it?
Answer
Yes, indeed, for no sin is greater or provokes God's wrath more than the profaning of his name. That is why he commanded it to be punished with death.
Scripture references
Question 100 of 129
Study it, question by question
Bosko turns the catechism into a few minutes a day — one question at a time, spaced so the answers actually stick, with an AI companion grounded in the Reformed tradition to talk through whatever you don't yet grasp.