1. This precept, as well as its predecessor, consists of a command, and of its sanction through the threatening of a punishment. The precept is a negative one, and prohibits a deed which is displeasing to God, in these words: "Thou shalt not take the name of the Lord thy God in vain."
2. The reason, and end of the precept is this: Because God is entirely holy, and because his name is full of majesty, we must use it in a holy and reverend manner, and must, by no means, account it common or contaminate it.
3. "The name of God" is here received in its most general notion, for every word which, according to the purpose God, is used to signify God and divine things.
4. "To assume" or "to take the name of God," properly, to take that word into our mouth and pronounce it with our tongue. If, under this phrase, any one, by a synecdoche, is desirous, likewise, of comprehending the deeds, in which God and divine things are less religiously treated, he has our full permission; and, we think, he does not depart from the sense of the precept. But we still continue in the explanation of the proper acceptation.
5. The particle, "in vain," is variously received — for that which is done rashly and without just cause — for what is done in vain and with no useful end — for what is done with mendacity, dissimulation, falsely, inadvertently, etc. Hence, this prohibition likewise diffuses itself extensively in every direction.
6. But, perhaps with some propriety, every "taking of the name of the Lord in vain" may be reduced to two principal heads or kinds: The First genus comprehends the use of the name of God when no mention of it, whatever, should be made; that is, in a word or deed, in which, it has been the will of God that the mention of his name shall not intervene, either because the word or deed is not lawful, or because it is of minor moment.
7. But the Second genus comprises the incorrect use of the name of God; that is, when it is not truly used in any of our duties in which it may be lawfully used, or in which it ought also to be dutifully used according to the divine direction.
8. The duties of this class are, the adoration and invocation of God, the narration and preaching of his word or of divine things, oaths, etc. in these, the name of God is taken in vain, in three ways:
(1.) Hypocritically, when it is not used sincerely from the whole heart.
(2.) With a doubting conscience, when it is used with an uncertain belief that it is lawful to be used in that duty.
(3.) Against conscience, as when it is employed to bear testimony to a falsehood.
9. The threatening is expressed in these words: "For the Lord will not leave him unpunished that taketh his name in vain." By this he endeavors to persuade men, that no one should dare to use his name; of which persuasion there is so much the greater necessity, as the heinousness of this offense is not sufficiently considered among men.