I agree with the muzzle. I have a black lab mix who is getting ornery in her old age. Has never liked baths, so I muzzle her to keep from biting me. Once she's in the tub, it's all good..and the muzzle comes off.
No, I'm the first owner. I've had him since he was a puppy. He would try to run away when bath time came but he never tried to bite. I would put him in the tub and talk to him and try to comfort him just like I had done with all my other dogs through life.
You may wan to try putting him in the tub with no water and just make him sit there, until he gets used to that. Then try water in the tub a couple of times (I usually only have an inch or two of water in the tub). Then try putting water on him. Then after a couple more times put shampoo on him.