GEN662 When mora [this verse] and its equivalent, yirah, became identified with fear and hence contrasted with ahavah, love, the question of the relative merits of love and fear of God arose. Though serving God out of fear seems, on the face of it, to be superior to serving Him out of fear, Scripture and some rabbinic sources use the two terms indiscriminately when speaking of what man’s attitude should be toward God. Thus, commenting on the verse “And thou shalt fear the Lord,” the Midrash says: “Be like those three of whom it is written that they fear the Lord.  Be like Abraham (Genesis 22:12), Joseph (Genesis 42:18), and Job” (Job 1:1). Tanhuma (Buber ed.) comment on Lev 5:1, p. 9, par. 15.  On the other hand, Rabbi Simeon ben Elazar (second half of second century C.E.) quotes Scripture to prove that “he who serves a God out of love is superior to one who serves God out of fear, for Scripture ascribes a greater reward to him.” Sotah 31a  Thus also we are led to believe that Rabban Yohanan ben Zakkai was unhappy at the thought that Job served God out of fear rather than out of love. Sotah 27b GREENBERG 80-1