21 Jesus answered them, “I tell all of you with certainty, if you have faith and do not doubt, not only will you be able to do what has been done to the fig tree, but you will also say to this mountain, ‘Be removed and thrown into the sea,’ and it will happen.
Matthew 21:21 Cross References - ISV
Matthew 8:12
12 But the unfaithful heirs of that kingdom will be thrown into the darkness outside. In that place there will be wailing and gnashing of teeth.”
Matthew 17:20
20 He told them, “Because of your lack of faith. I tell all of you with certainty, if you have faith like a grain of mustard seed, you can say to this mountain, ‘Move from here to there,’ and it will move, and nothing will be impossible for you.
Mark 11:22-23
Luke 17:6-7
6 The Lord replied, “If you have faith the size of a mustard seed, you could say to this mulberry tree, ‘Be uprooted and planted in the sea,’ and it would obey you!
7“Suppose a man among you has a servant plowing or watching sheep. Would he say to him when he comes in from the field, ‘Come at once and have something to eat’?
7
Romans 4:19-20
19 His faith did not weaken when he thought about his own body (which was already as good as dead now that he was about a hundred years old) or about Sarah’s inability to have children,
20 nor did he doubt God’s promise out of a lack of faith. Instead, his faith became stronger and he gave glory to God,
1 Corinthians 13:2
2 If I have the gift of prophecy and can understand all secrets and every form of knowledge, and if I have absolute faith so as to move mountains but have no love, I am nothing.
James 1:6
6 But he must ask in faith, without any doubts, for the one who has doubts is like a wave of the sea that is driven and tossed by the wind.