Luke 17:5-6

5The apostles said to the Lord, “Increase our faith [our ability to confidently trust in God and in His power].”

6And the Lord said, “If you have [confident, abiding] faith in God [even as small] as a mustard seed, you could say to this mulberry tree [which has very strong roots], ‘Be pulled up by the roots and be planted in the sea’; and [if the request was in agreement with the will of God] it would have obeyed you.