Does not the very nature of things teach you that if a man has long hair, it is a disgrace to him, but that if a woman has long hair, it is her glory? For long hair is given to her as a covering.  If anyone wants to be contentious about this, we have no other practice—nor do the churches of God. 1 Corinthians 11:14-16

            The traditional law of the Jews indicated that men cut their hair.  They grew it long only if they took a Nazirite vow or shaved it off when they made a promise.  Paul, writing to the Corinthians, supported this custom even in a non-Jewish environment. 

            Long hair was a custom in other cultures, traditionally pagan, and Paul didn’t want any association to that.  Long hair also bended gender distinctions and Paul wanted to keep male and female identities separate.

            Today those cultural distinctions are different in our society and long hair is more acceptable.  Other gender benders are more controversial than long hair.