Yetzer hara

In Judaism, yetzer hara (Hebrew: יֵצֶר הַרַע, romanizedyēṣer haraʿ) is a term for humankind's congenital inclination to do evil. The concept is prominent in rabbinic texts and in the works of the Syriac poet Narsai. The term itself is drawn from the phrase "the inclination of the heart of man is evil" (Biblical Hebrew: יֵצֶר לֵב הָאָדָם רַע, romanized: yêṣer lêḇ hā-ʾāḏām raʿ), which occurs twice at the beginning of the Torah in Genesis 6:5 and Genesis 8:21 .

The Hebrew word yetzer, having appeared twice in Genesis, occurs again at the end of the Torah: "I knew their devisings that they do". Thus from beginning to end, the heart's yetzer (plan) is continually bent on evil. However, the Torah which began with blessings also anticipates future blessings, which will come as a result of God circumcising the heart in the latter days.