Belief in oneself (read sometimes as belief in God) can help one overcome any hurdle in life's path.

Alternative spelling of O ye of little faith

A response to an expression of doubt or uncertainty.

Alternative spelling of O me of little faith

(humorous) Drawing attention to one's own doubt or skepticism.

Lacking faith; lacking belief in something. / Not believing in God, religion, or a comparable ideology. / Unfaithful (said of people, towards their partners) / Not observant of promises or covenants.

(UK) A polite, formulaic end to a letter, used especially when the sender does not know the recipient's name, for example in a business letter.

In a faithful manner. / (US) A conventional formula for ending a letter, used when the salutation addresses the person for whom the letter is intended using an honorific.

In a faithless manner

The quality of being faithless.