After reading Hayduke's 3 most recent posts, I left the longest comment. This led me to the dictionary.

DOUBT

1. to be uncertain about; consider questionable or unlikely; hesitate to believe.
2. to distrust.
3. Archaic. to fear; be apprehensive about. –verb (used without object)
4. to be uncertain about something; be undecided in opinion or belief. –noun
5. a feeling of uncertainty about the truth, reality, or nature of something.
6. distrust.
7. a state of affairs such as to occasion uncertainty.
8. Obsolete. fear; dread.

FAITH

1. confidence or trust in a person or thing: faith in another's ability.
2. belief that is not based on proof: He had faith that the hypothesis would be substantiated by fact.
3. belief in God or in the doctrines or teachings of religion: the firm faith of the Pilgrims.
4. belief in anything, as a code of ethics, standards of merit, etc.: to be of the same faith with someone concerning honesty.
5. a system of religious belief: the Christian faith; the Jewish faith.
6. the obligation of loyalty or fidelity to a person, promise, engagement, etc.: Failure to appear would be breaking faith.
7. the observance of this obligation; fidelity to one's promise, oath, allegiance, etc.: He was the only one who proved his faith during our recent troubles.
8. Christian Theology. the trust in God and in His promises as made through Christ and the Scriptures by which humans are justified or saved.