(Numb. 1:1) “Then the Lord spoke unto Moses in the Sinai desert.” [Sinai] was called by six names: Mountain of God (as in Ps. 68:16), Mount Bashan (ibid.), Mountain of Peaks (ibid.), Mountain of Desire (hmd), Mount Horeb (Exod. 3:1; 33:6; etc.), and Mount Sinai. The Mountain of God is [so called] because on it God sat in judgment, as stated (in Exod. 21:1), “Now these are the judgments which you shall set before them.”
Mount Bashan is the mountain where (sham) Holy One, blessed be He, came (ba'). The Mountain of Peaks (gavenunnim, rt.: gbn) is the mountain where He disqualified all the [other] mountains, just as you say (in Lev. 21:20), “or a hunchback (gbn) or a dwarf.” Mountain of Desire (rt.: hmd) is [so called], because on it the Holy One, blessed be He, desired (hmd) to dwell, as stated (in Ps. 68:17), “the mountain God desired for His dwelling.” Mount Horeb (rt.: hrb) is [so called], because upon it the sword (rt.: hrb) [of judgment] was unsheathed, as stated (in Lev. 20:10), “the adulterer and the adulteress shall surely be put to death,” [and] (in Numb. 35:16), “the murderer shall surely be put to death.”
Mount Sinai is [so called], because on it the peoples of the world became hateful (rt.: sn') to the Holy One, blessed be He; and He rendered a verdict against them, as stated (in is. 60:12), “and the gentiles shall be utterly (hrb) destroyed (rt.: hrb).” R. Abba bar Kahana said in the name of R. Johanan, “’And the gentiles shall be utterly destroyed’ – it was where they received a verdict.”