Albert Barnes Commentary John 4:2

"(although Jesus himself baptized not, but his disciples)," — John 4:2 (ASV)

Though Jesus himself baptized not. The reason why Jesus did not baptize was probably because, if he had baptized, it might have made unhappy divisions among his followers: those might have considered themselves most worthy or honoured who had been baptized by him. (Compare to 1 Corinthians 1:17).