how to teach the unbreakable horse

Question
well my friend bought a horse about 9  months ago he is what my friend calls the unbreakable horse i know theres no such thing. When you try to touch his but he quivers and this is a problem when you try and get on and ride. he likes to blot and has no rein control what so ever. she wants to know how to get him with rein control and he has another issue its with me he likes to rear and take control i by no means will ever accept this behavior form any horse regardless of how old it is so we want to know how to get him started and what bit to use hes a 4 year old begin,draft,cob about 13.3-14 hands thanks

Answer
Hi Chelsea!

I understand from your question that you are not the owner of the horse.  I cannot give training advice to non-owners about the horse in question.

I will say, however, in the broadest of terms....that from the short amount you wrote, it would be best for the horse if he was handled by a professional trainer.

Good luck and remember to always wear an ASTM/SEI approved helmet!

Solange