"Must believe"

1. Heb. 11: 6
     6 But without faith it is impossible to please him: for he that cometh to God must believe that he is, and that he is a rewarder of them that diligently seek him.
2. Alma 33: 13
     13 Behold, if ye do, ye must believe what Zenos said; for, behold he said: Thou hast turned away thy judgments because of thy Son.