Faith

Verily I say unto you my friends, fear not, let your hearts be comforted; yea, rejoice evermore, and in everything give thanks; Waiting patiently on the Lord, for your prayers have entered into the ears of the Lord...and are recorded with this seal and testament--the Lord hath sworn and decreed that they shall be granted. Therefore, he giveth this promise unto you, with an immutable covenant that they shall be fulfilled; and all things wherewith you have been afflicted shall work together for your good, and to my name's glory, saith the Lord.

Doctrine & Covenants 98:1-3