The Exposition of the Third Commandment
Leviticus 19:12; Deuteronomy 6:13; 10:20
Leviticus 19
12. And ye shall not swear by my name falsely, neither shalt thou profane the name of thy God: I am the LORD.
Deuteronomy 6
13. … shalt swear by his name.
Deuteronomy 10
20. … swear by his name.
Leviticus 19:12. And ye shall not swear by my name falsely. Although Moses is treating of the duties of the Second Table, and had previously forbidden men to deal fraudulently with their neighbors, he still adds this sentence by way of confirmation. It may, however, be inferred from the second clause of the verse that He directly had regard to the glory of God when he says, “Thou shalt not profane the name of thy God.” For raging greediness after gain causes the avaricious and rapacious man not only to defraud men, but to become insolent to God Himself. Moses, therefore, although he is professedly condemning the falsehood and deceit whereby our neighbors are injured, at the same time takes occasion to introduce the declaration that we must beware lest, whilst covetousness impels us to do wrong, injury should be done not only to men but to God Himself also. The word used here, however, is not שוא, shau, as before, but שקר, sheker, which properly signifies deceitfulness; and therefore I have said that it enjoins us to beware lest any one by his perjury should do any injury to his neighbor; nevertheless, that this prohibition has direct reference to the Third Commandment, since Moses especially insists on this point, that God’s name is profaned by perjury, and thus he not only inculcates integrity, but also has regard to religion, that God’s majesty may not be violated. The expression is worthy of notice, “Thou shalt not pollute the name of God,” because God, who is eternal and immutable truth, cannot be more grossly insulted than by being summoned as a witness to falsehood, which is assuredly a shameful and wicked pollution. This was not regarded by the heathen, who, although they pretended to reverence God’s name in their oaths, yet made no scruple of deceiving, if he whom they had promised deserved it. Thyestes in the poet says, “I never have pledged my faith, nor do I pledge it to any faithless person;” 1 since his brother was a villain, he considered that he lay under no valid obligation to him. This is as if God’s majesty were dependent upon men’s deservings, so that it was allowable to call Him to witness whilst we deal deceitfully. Let this, then, be our firm conclusion, that in our oaths God is first to be regarded, whose holy name is more precious than a hundred worlds.
Exodus 23:13
Exodus 23
13. … and make no mention of the name of other gods, neither let it be heard out of thy mouth.
13. Make no mention of the name of other gods. There is no sort of doubt but that this declaration should be connected with the Third Commandment. Moses explains that God’s name is taken in vain and abused, if men swear by other gods; for it is not lawful to refer the judgment of things unknown to any other than the one true God. Consequently, the glory of the Deity is transferred to those by whose name men swear. Therefore by the Prophet God pronounces a severe denunciation, that He will destroy all those that swear by His name, and also by Malcham, (Zephaniah 1:5,) since thus the Jews mixed Him up with their idol, and so profaned His holiness. In sum, since by swearing we profess that He is our God, whom we declare to be both the knower of our hearts and the judge of our souls, the true God justly claims this honor for Himself alone, inasmuch as the glory of His name is detracted from, not only if we speak less reverently than we should of Him, but also if we associate with Him such as may usurp a part of His rights. And this more clearly appears from the two passages which we have adduced from Deuteronomy, wherein the people are commanded to swear by the name of the one God, which is equivalent to rendering to His sacred name in our outward profession of service the unmixed reverence which it deserves. 2 Still God does not exhort the people to indulge themselves freely in oaths, as if by frequent oaths they exercised themselves in the duties of piety, but simply means that when there is occasion for it or necessity, and a just cause shall demand it, they must swear in no other way than by invoking Him alone as their witness and judge.