If you were not doubtful, you would not need faith! Being doubtful encourages faith.
Ever hear of a book called Radio Replies, the following is an interesting comment on "doubt" from that book...
Highly intellectual men do accept the doctrines of Christianity as certain. Being highly intellectual, they have not done so without profound investigation of the reasonable grounds for their position. And knowing that such men are convinced, it is not highly intellectual conduct to reject as legends and fairy tales the doctrines they accept, without making a similar investigation.