Verse 12: But above all things, my brethren, (Matt. 5:34, etc.) swear not, neither by heaven, neither by the earth, neither by any other oath: but let your yea be yea; and your nay, nay; lest ye fall into condemnation.
[Before all things] That is, before the other matters attend to this (Drusius, Gataker, thus Estius): Great vigilance is needed on account of the contrary custom (Estius), not to be easily rooted out: The Jews were very prone to oaths. Now, what things we greatly desire to be avoided, we are wont to say that these things are to be avoided before all (Grotius). James dissuades from impatience, and from its effects, whether with respect to men, as in verse 9, or with respect to God, as in this place. Now, he warns that this sin is the greatest, not simply, as if were greater than adultery, murder, etc., but comparatively, with respect to the other fruits of impatience, concerning which verse 9; that is to say, If perhaps impatience causes you to murmur, etc., beware especially that it draw you not away to the abuse of the name of God (Gataker).
Above all things, etc.: Because it is a great sin to swear upon every slight occasion, and it was very usual among the Jews, and it was the more difficult to bring them off from it who were so much accustomed to it; therefore the apostle commands them, that above all things they should not swear, i.e. should take special care they did not, and watch diligently against a sin so many were addicted to, and into which they might so easily fall.
[Swear not] Namely, by promising anything concerning an uncertain matter. Not that there is not also to be an abstaining from an assertory oath, as far as the honor of God and the commands of superiors allows it; but that the context of the sentence shows that he does not treat of that here. Also, the Essenes were abstaining from such oaths, and, following their example, the Pythagoreans. See what things we said on Matthew 5:33, etc., and Concerning the Law of War and Peace 2:13, 21 (Grotius). Now, oaths are prohibited, not simply and absolutely (Estius, Gataker), for they are made use of by men most holy both in the Old and in the New Testaments, Genesis 21:23, etc.; 26:28; 1 Kings 17:1; 2 Corinthians 1:23; Galatians 1:20; 1 Thessalonians 2:5, 10: and the use of them is permited and approved by God, Exodus 22:8, 10, 11; Leviticus 5:4; Numbers 5:19, 20; Psalm 15:4; Proverbs 18:18; Hebrews 6:16: but rather oaths precipitous, arising from impatience, 1 Kings 19:1, 2, rash, Leviticus 5:4; Jeremiah 5:2, common (Gataker), or in familiar and daily speech (Estius, Gataker), Matthew 5:37, vain and without just cause (Gataker). There is to be an abstention from oaths always and altogether, as far as it is able to be done by us, and unless just necessity compels (Estius). Swearing is not to be done lightly and rashly (Tirinus). For in this are profanity and atheism (Gataker), irreverence for the Divine name (Estius, Gataker), the indignity of the contempt of our souls against God, for they, having been provoked by men, fly into the face of God (Gataker).
Swear not; all swearing is not forbidden, any more than Matthew 5:34; (for oaths are made use of by holy men both in the Old and New Testament, Genesis 21:23, 24; 24:3; 26:28; 1 Kings 17:1, 2; 2 Corinthians 1:23; Galatians 1:20; and the use of an oath is permitted and approved of by God himself, Psalm 15:4; Hebrews 6:16;) but such oaths as are false, rash, vain, without just cause, or customary and frequent in ordinary discourse, 1 Kings 19:2; Jeremiah 5:2; Matthew 5:37.
[Neither by, etc., μήτε τὸν οὐρανόν, etc.] Νὴ/by is understood, although the Greeks do say ὀμνύναι, to swear, both τὸν Δία, and νὴ τὸν Δία, by Zeus (Piscator). These oaths were exceedingly common at that time (Gataker), among the Jews (Estius, Gataker), either because they were thinking that thus there was no sin against the third Commandment (Gataker); or because they believed that those were able to be violated without great sin (Gataker, similarly Estius). The more superstitious Jews were not using the name of God expressly for common oaths, but other things, like Heaven and Earth. But Christ wills that there be an abstention from these also. For, just as Ulpianus said that he who swears by his salvation appears to swear by God, because he swears with regard to the Divine name; so also he who swears by Heaven prays that Heaven be insalubrious for him, should he fail; and he who swears by Earth prays that Earch be unfruitful to him, should he fail: all which depend upon God (Grotius). There is sin in oaths of this sort, whether, 1. in them respect be had to God; or, 2. we have regard only to the matters themselves, not to God. For thus there is a more grievous sin. To swear by creatures directly is simply unlawful, because in this we attribute to creatures what is proper to God, that is, that they know our hearts, that they are superior to our souls. An oath is a principal part of Divine worship, Deuteronomy 6:13; Jeremiah 5:7, and a type of invocation (Gataker). It is a corruption akin to idolatry, since either the power of judging, or the authority of proving testimony, is conferred upon them (Gataker out of Calvin)
Neither by heaven, neither by the earth; by which the Jews thought they might lawfully swear, as likewise by other creatures, so the name of God were not interposed; not considering that where it is not expressed yet it is implied, Matthew 23:20, 21.
[Neither by another, etc.] For example, by Jerusalem, by the Temple, or Altar, by κορβᾶν/corban, by your own Head, Matthew 5:36; 23:16, 22 (Grotius), μὰ νεφέλας, by the clouds, μὰ δίκτυα, by their nets, μὰ παγίδας, by their traps, μὰ τὰ λάχανα, by the herbs, in Suidas. Now, now mention is made of creatures obliquely in the formulas of oaths, either, 1. by solemn appeal, as far as the glory of God shines in them, as it does through the heavens, etc.; or, 2. by giving in pledge, by things dear to us, and by the head, by the soul, etc.; or, 3. by imprecation, as by this bread, that is to say, let this bread be poison to me (Gataker).
Neither by any other oath; viz. of the like kind.
[Let it be…yea yea, etc.] That is, let your Affirmation, or Negation, be simple and unembellished (Estius), by saying either Yes, or No (Piscator), not sworn (Estius). Others: Constantly and simply affirm truths, and deny falsehoods (Castalio), both in statements, and in promises. It shall be done in such a way that ye merit confidence without oaths (certain interpreters in Estius). What ye promise in word, fulfill in deed, whether it consist in doing, or in not doing. Ναὶ/yea signifies both a Promise, and the fulfillment of a Promise, as it is seen in 2 Corinthians 1:18-20. Therefore, there is here πλοκὴ, a harmony, as in a similar saying of the Jews, The Just man’s אִין/Yea is אִין/Yea, and No is No. That אִין is of one promising, as ναὶ or μάλιστα/certainly is to the Greeks (Grotius).
But let your yea be yea; and your nay, nay: either, 1. Let your speech be yea, yea, and nay, nay; i.e. by plain affirmations and negations, without the addition of any oath for confirmation, Matthew 5:37: or, 2. Let your yea be yea, and your nay, nay, i.e. let your words be in truth and sincerity, your speech seconded by your actions; accustom yourselves to truth and plainness in speaking, and that will take away the occasion of swearing. See the like, 2 Corinthians 1:17-19.
[Lest, etc., ἵνα μὴ ὑπὸ κρίσιν πέσητε] So it is read by the Syriac, and the Arabic, and the Latin (Grotius), and by one old Manuscript codex (Beza), and a codex of Robert, and in the margin of the Royal Bible (Estius). [Now, thus they translate it:] Lest ye fall into condemnation (Beza, thus Illyricus, Pagnine, Piscator, Menochius), or, under judgment (Tremellius out of the Syriac, Estius, thus the Vulgate), namely, of condemnation (Estius, thus Menochius), on account of the violated law of God concerning not swearing (Estius). Lest ye be liable to judgment by swearing rashly (Dieu). Κρίσις/judgment in the place of κατάκρισις/condemnation, judgment against (Piscator). Others read, ἵνα μὴ εἰς ὑπόκρισιν πέσητε, as the Complutensian edition has it (Vorstius). [Thus Grotius, Vorstius, etc. Now, thus they render it:] Lest ye fall into hypocrisy (Erasmus, Tigurinus, Castalio, Arabic); that is, Lest ye be discovered as feigners of probity (Vatablus). Lest ye be found liars. Thus lest I lie, Proverbs 30:9. For ὑπόκρισις/hypocrisy is taken for lying in 1 Timothy 4:2; and ὑποκρίνεσθαι is in the place of to lie in Symmachus’ version of Proverbs 16:28; and ὑποκριτὴς in Job 34:30 and 36:13. It appears that this express, not having been well comprehended, was the cause of the other reading (Grotius).
Lest ye fall into condemnation; viz. for taking the name of God in vain, Exodus 20:7, which is always done in an unwarrantable oath.
 Greek: Πρὸ πάντων δέ, ἀδελφοί μου, μὴ ὀμνύετε, μήτε τὸν οὐρανόν, μήτε τὴν γῆν, μήτε ἄλλον τινὰ ὅρκον· ἤτω δὲ ὑμῶν τὸ ναί, ναί, καὶ τὸ οὔ, οὔ· ἵνα μὴ ὑπὸ κρίσιν πέσητε.
 That is, an oath pertaining to the past or present, but not to the future.
 The Essenes were an ascetic Jewish sect, flourishing from the second century BC to the first century AD.
 With the Accusative of the person or thing by which one swears.
 For example, Aristophanes’ Plutus 202. The meaning is not affected by the presence or absence of the preposition.
 Exodus 20:7: “Thou shalt not take the name of the Lord thy God in vain; for the Lord will not hold him guiltless that taketh his name in vain.”
 Domitius Ulpianus (c. 170-228 AD) was a Roman jurist.
 See Mark 7:11.
 Thus Codex Sinaiticus, Alexandrinus, and Vaticanus.
 Robert Estienne (1503-1559) was a printer and classical scholar in Paris. He published the Royal Codex in 1550, an edition of the Greek New Testament, called the Editio Regia because of the handsome Greek font used in the printing.
 Thus the overwhelming majority of Byzantine manuscripts.
 Proverbs 30:9: “Lest I be full, and deny (וְכִחַשְׁתִּי, and deceive), and say, Who is the Lord? or lest I be poor, and steal, and take the name of my God in vain.”
 1 Timothy 4:2: “Speaking lies in hypocrisy (ἐν ὑποκρίσει ψευδολόγων); having their conscience seared with a hot iron…”
 Job 34:30: “That the hypocrite (אָדָ֥ם חָנֵ֗ף; ἄνθρωπον ὑποκριτὴν, in the Septuagint) reign not, lest the people be ensnared.”
 Job 36:13: “But the hypocrites in heart (וְֽחַנְפֵי־לֵ֭ב; καὶ ὑποκριταὶ καρδίᾳ, in the Septuagint) heap up wrath: they cry not when he bindeth them.”