Faith carries the notion of confidence,  trust, and assurance in God.  Faith gives the believer a conviction that what he expects in faith, will come to pass

"Now faith is the assurance of things hoped for, the conviction of things not seen." Hebrews 11:1

"And without faith it is impossible to please Him, for whoever would draw near to God must believe that He exists and that he rewards those who seek him." Hebrews 11:6

He said to them, “Because of your little faith. For truly, I say to you, if you have faith like a grain of mustard seed, you will say to this mountain, ‘Move from here to there,’ and it will move, and nothing will be impossible for you.” Matthew 17:20 ESV 

He did not waiver at the promise of God through unbelief, but was strengthened in faith, giving glory to God. Roman 4:20 NKJV

"So faith comes from hearing, and hearing through the word of Christ. Romans 10:17 ESV