You shall not take the name of the LORD your God in vain, for the LORD will not leave anyone unpunished who takes His name in vain.
Exodus 20:7. Thou shalt not take the name. There is a manifest synecdoche in this Commandment; for in order that God may procure for His name its due reverence, He forbids its being taken in vain, especially in oaths. Whence we infer on the other hand an affirmative commandment, that every oath should be a testimony of true piety, whereby the majesty of God Himself should obtain its proper glory.
Here is, I. The preface of the law-writer, Moses: God spoke all these words, Exo 20:1. The law of the ten commandments is, 1. A law of God's making. They are enjoined by the infinite eternal Majesty of heaven and earth. And where the word of the King of kings is surely there is power. 2. It is a law of his own speaking.
Commenting on Exodus 20:1-11
Thou shall not take the name of the Lord God in vain,.... Make use of the name Lord or God, or any other name and epithet of the divine Being, in a light and trifling way, without any show of reverence of him, and affection to him; whereas the name of God ought never to be mentioned but in a grave and serious manner, and...