GEN23 Reverence (mora) for your teacher should be like the reverence for Heaven. Pirkei Avot IV:15 … By [Scripture’s] account of Creation, the raki’a, the firmament, was needed to separate a collective oceanic mass into the upper waters of heaven and waters of the earth.  Otherwise, life could not exist on this earth, for all would remain under water. Yet a wedge was thus driven between elements which belonged naturally together.  Like was separated from like.  Therefore the Torah could not say ki tov, to stamp it with full approval.  Wherever, however divineness enters between like and like, between brother an brother, between man and his fellow man, it is hard to bear, and cannot be wholly good.  Interestingly, enough, the firmament, raki’a, became shamayim, the heaven, as we read in [this] verse. Our Sages explain that the word shamayim is derived from a composite of esh, fire, and mayim, water, for these are the two elements of which the heaven is composed. This fascinating concept brings to mind such phenomena as the sudden changes from extreme heat to extreme cold that occurs in outer space, and the conjunction of lightning and rain in the heavens.  We see then, that as the aftermath of a necessary division, which makes Scripture withhold the words ki tov, “that it was good,” the Almighty constructs a heaven wherein normally conflicting elements of fire and water are joined.  After machloketh, division, we have machloketh, conflict between two inimical elements that must remain united to form a heaven, to serve the Almighty in His cosmic purpose.  For this reason, say the Sages, Job praises the Creator that “He makes peace in His supernal realms.” If fire and water can cooperate to maintain the heavens, surely the stormy temperament and combustible personality of the most volatile of men can be controlled and disciplined to work toward a heaven on earth.  Indeed, toward this goal and dream we entreat His aid in our daily prayers: “He who makes peace in His supernal realms, may He provide peace for us and for all the people Israel; and say Amen.”  SINAI2 110-1