Romans 12:3
3 For I say, through the grace given to me, to everyone who is among you, not to think of himself more highly than he ought to think, but to think soberly, as God has dealt to each one a measure of faith.
Romans 10:17
17 So then faith comes by hearing, and hearing by the word of God.
Luke 17:5-6
5 And the apostles said to the Lord, "Increase our faith."
6 So the Lord said, "If you have faith as a mustard seed, you can say to this mulberry tree, ‘Be pulled up by the roots and be planted in the sea,' and it would obey you.
Examples: Abraham
Mark 11:24
24 Therefore I say to you, whatever things you ask when you pray, believe that you receive them, and you will have them.
2 Corinthians 5:7
7 For we walk by faith, not by sight.
Hebrews 11:1
1 Now faith is the substance of things hoped for, the evidence of things not seen.
Matthew 13:18-23
18 "Therefore hear the parable of the sower:
19 When anyone hears the word of the kingdom, and does not understand it, then the wicked one comes and snatches away what was sown in his heart. This is he who received seed by the wayside.
20 But he who received the seed on stony places, this is he who hears the word and immediately receives it with joy;
21 yet he has no root in himself, but endures only for a while. For when tribulation or persecution arises because of the word, immediately he stumbles.
22 Now he who received seed among the thorns is he who hears the word, and the cares of this world and the deceitfulness of riches choke the word, and he becomes unfruitful.
23 But he who received seed on the good ground is he who hears the word and understands it, who indeed bears fruit and produces: some a hundredfold, some sixty, some thirty."