"And you shall love the L-rd your G-d with all your heart, with all your
soul, and with all your might (me'od)" (Deuteronomy 6:4). "With all your
heart" -- with both your inclinations, with your good inclination and with your evil inclination. "With all your soul" -- even to the point that someone takes your life....
Talmud, Berachot 54a