“Stop being afraid of spiders!” I yell at you. If you are afraid of spiders, does that work? Just because I tell you to? Or should I just let you get over that fear by letting you hang out with spiders right in your face? Or should I yank you in the neck to stop you from crying? I think not. In fact, I think you might start getting an anxiety attack. So don’t do that to your fearful dog. Learn the right way to counter condition or desensitize your dog to the thing he fears. Consult a positive, reward-based, force-free trainer who understands dog behavior.
[More later, on things you can teach your dog to build confidence and reduce fear.]