Q. What are the sins forbidden in the third commandment?
A. The sins forbidden in the third commandment are, the not using of God’s name as is required; and the abuse of it in an ignorant, vain, irreverent, profane, superstitious or wicked mentioning or otherwise using his titles, attributes, ordinances, or works, by blasphemy, perjury; all sinful cursings, oaths, vows, and lots; violating of our oaths and vows, if lawful; and fulfilling them, if of things unlawful; murmuring and quarrelling at, curious prying into, and misapplying of God’s decrees and providences; misinterpreting, misapplying, or any way perverting the Word, or any part of it; to profane jests, curious or unprofitable questions, vain janglings, or the maintaining of false doctrines; abusing it, the creatures, or anything contained under the name of God, to charms, or sinful lusts and practices; the maligning, scorning, reviling, or any wise opposing of God’s truth, grace, and ways; making profession of religion in hypocrisy, or for sinister ends; being ashamed of it, or a shame to it, by unconformable, unwise, unfruitful, and offensive walking, or backsliding from it.
(Question CXIII of the Westminster Larger Catechism.)