Musar zu Mischlej 24:8

“So that you do not follow your heart and your eyes” (Numbers 15:39). We were warned with this not to think to do a transgression (or upon any) [or any] prohibition or sin - like the matter that is stated (Proverbs 24:8), “He who thinks to do evil” - and not to think about words of heresy, lest one stumble and be drawn after them. And when he places upon his heart that God, may He be blessed, examines the heart and investigates the kidneys (understood as the seat of wisdom), how can he dare to defile his heart and [have] a ruffian matter lodged upon it? And King Solomon, peace be upon him, said (Proverbs 24:9), “The schemes of folly are sin.” He also said (Proverbs 6:16-18), “Six things the Lord hates; seven are an abomination to His soul: [...] A mind that hatches evil plots.”