Proverbs 12:20 (BSB)

Deceit is in the hearts of those who devise evil, but the counselors of peace have joy.

From Proverbs 12. Also in the ESV.

Commentary on Proverbs 12:20

• Matthew Henry (Presbyterian), Matthew Henry's Complete Commentary on Proverbs 12:20: Note, 1. Those that devise mischief contrive, for the accomplishing of it, how to impose upon others; but it will prove, in the end, that they deceive themselves. Those that imagine evil, under colour of friendship, have their hearts full of this and the other advantage and satisfaction which they shall gain by it, but it is all a cheat.
• John Gill (Reformed Baptist), Exposition of the Old and New Testaments on Proverbs 12:20: Deceit is in the heart of them that imagine evil,.... That secretly devise mischief in their hearts against their neighbours; that plough evil, as the word (g) signifies, and sow discord among men; and by many artful and deceitful methods promote contention and division, in order to answer some base designs of theirs; but sooner or later they are deceived themselves, are disappointed of their...
• Jamieson-Fausset-Brown (Reformed), Commentary Critical and Explanatory on the Whole Bible on Proverbs 12:20: that imagine--or, "plan" (Pro 3:29). They design a deceitful course, to which, with all its evils and dangers to others and themselves, the happiness of peace-makers is opposed (compare Mat 5:9; Rom 12:18).
• Keil & Delitzsch (Lutheran), Biblical Commentary on the Old Testament on Proverbs 12:20: Pro 12:20 20 Deceit is in the heart of him who deviseth evil, But those who devise peace cause joy. Regarding the figure of forging, fabricating (lxx, Aquila, Symmachus, and Theodotion, τεκταίνειν), or of ploughing, which underlies the phrase חרשׁ רע, moliri malum, vid., at Pro 3:29.