Whether Howie is a tender terrier or a gentle giant, he may still be a bit skittish when the time comes to be groomed. If you adopted your new family member as a pup, you should spend as much time as you can getting Howie used to being touched. This will make things go far more smoothly when the time comes to start grooming him. For older dogs that may have a good reason (at least in their minds) to balk at the idea of being groomed, keep in mind you can teach any dog to enjoy being groomed, it just takes time and patience.
In no way does Howie want to upset you, or worse yet hurt you, but there is something about those shiny tools you have in your hands that makes him nervous. Grooming isn't like being played with or having a good belly rub to him. Until he gets used to the process and the tools, he is going to need a little help from you.
Since Howie is such a gentle dog, your chances of being bitten are probably nil. But, you still need to work with him if you want him to learn to enjoy the process. Grooming weekly is a great way to get him used to being groomed and in time come to love it. Take your time, make it fun, and think of it as a great way for the two of you to bond.