Thank you for your replies.

I have read so many people online in different places saying to bite them back. While I may resort to that eventually, I personally feel that its not something I want to try right now. If your child smacks you in the face or does something else that hurts you, you wouldn't do it back to them. It would seem to me like we are telling them this behaviour is ok sometimes. But I totally understand why people do it!!

I like the idea of shoving his own arm/hand in his mouth. I might give that a go next time he tries to bite.

Who knows, maybe I will resort to giving him a nip eventually!

Thank you all for your replies!! I appreciate all of this advice!!