D&C 63

 The Lord addresses faith and its relationship with signs - 

"...he that seeketh signs shall see signs, but not unto salvation.

8 Verily, I say unto you, there are those among you who seek signs, and there have been such even from the beginning;

9 But, behold, faith cometh not by signs, but signs follow those that believe.

10 Yea, signs come by faith, not by the will of men, nor as they please, but by the will of God.

11 Yea, signs come by faith, unto mighty works, for without faith no man pleaseth God; and with whom God is angry he is not well pleased; wherefore, unto such he showeth no signs, only in wrath unto their condemnation.

12 Wherefore, I, the Lord, am not pleased with those among you who have sought after signs and wonders for faith, and not for the good of men unto my glory."  (Doctrine and Covenants 63:7–12)

I specifically note - 

"...faith cometh not by signs, but signs follow those that believe..."

"...for without faith no man pleaseth God..."