Hanoverian that is very spooky?

I recently bought a 11 year old 16.3-17hh hanoverian gelding who was trained by Jill Henselwood and he is extremely spooky until he starts to jump and then he is fine, but before he spooks at everything and anything. I am wondering if it had to do with his training or maybe he was abused before because he seems especially spooky of people. He is a very high-end horse as in his bloodlines and lineage, he has also been stabled at some of the top barns in the world. Could any of this be a reason as to why he is so spooky? He also doesn't ride with a bit he gets extremely hot and even more spooky, and he is very sensitive in a bitless bridle so you cant pull on his face at all while riding him. Could all he need is a person to really trust to get him over all this spooky-ness or is there more to it?