GEN197 Rabbinic Judaism believes that man was initially endowed with good and evil tendencies Berachot 61a.  As a rational being, he must convert his evil impulse into a constructive force to serve the needs of society. In a midrashic interpretation of the Pentateuchal verse “And God saw everything that he had made, and behold, it was very good” [this verse], a rabbi alleged that “everything” is inclusive of the evil impulse. Had it not been for the evil impulse (lust), man would not take a wife, he would not procreate, and he would not establish a home. Shochar Tov on Ps. 9:1. One must therefore learn to serve God with both impulses, the good and the evil. Berachot 54a. BLOCH 203