GEN1066 Rashi [commentary on this verse] explains that they wanted the men for homosexual purposes, based on the previous uses of the verb “knowing” in the Torah as being associated with the sexual act. Genesis 4:1.   This was apparently common practice in that society, and hence this is the origin of the term “sodomy.”   All of these Torah examples [i.e., Potiphar bought Joseph for homosexual purposes Sotah 13b; commentaries of Genesis 6:12 RE each species “corrupted its way;” Noah’s grandson, Canaan, committed sin with him while Noah was drunk Genesis 9:22-24] have in common the fact that homosexual activity was common in these cultures and that God disapproved.   Consequently, some of these societies were eventually destroyed.  This, once again, shows that Jews may not engage in such activity and imitate the mores of these foreign societies.  AMEMEI 140