Biting

We used the book Little Dinos Don’t Bite and that really helped with LG biting spells.

We say "Teeth are for food not people" a lot. Solidly shake our heads as well as telling him it hurts us when he does that. It's usually a playtime thing here, too, so we stop actively playing with him when it happens. Now when he goes in for a bite, half the time he pulls back, shakes his head and says "no teeth"

Based on his age I would keep it as simple and clear as possible. In a stern but kind manner. Example: you can say "no bite mommy, we can bite food or bite toy" then if you can quickly find something else for him to bite or play with.

Developmentally, I don't think they're ready yet for lessons because emotions are a bit too complex for us to fully explain things to them.

I think thats a little harsh for a one and a half year old. He was more than likely being playful which is what they do at this age so in isolating him for that may be more traumatic than not. I agree with the other ladies in how to tell him and guide him not to do it.