Matthew 17:20

He answered them, "Because you have so little faith! For I solemnly say to you, if you have the faith that is living like a grain of mustard, you can say to this mountain, 'Move over from here to yonder,' and it will move over, and nothing will be impossible for you to do."

Luke 17:6

Then the Lord said to them, "If you had faith that grows like a mustard seed, you might have been saying to this mulberry tree, 'Pull yourself up by the roots and plant yourself in the sea,' and it would have obeyed you!

Matthew 13:31

He told them this story, as follows: "The kingdom of heaven may be compared to a mustard seed which a man took and sowed in his field.

Matthew 21:21

And Jesus answered them, "I solemnly say to you, if you have faith and do not doubt at all, you will not only do the sort of wonder done to the fig tree, but even if you say to this mountain, 'Get up and throw yourself into the sea,' it will be done.

Mark 11:23

I solemnly say to you, whoever says to this mountain, 'Get up and throw yourself into the sea,' and does not doubt at all in his heart, but has faith that what he says will take place, shall have it.

1 Corinthians 13:2

If I should have the gift of prophecy, And know all secret truths, and knowledge in its every form, and have such perfect faith that I could move mountains, but have no love, I am nothing.

Mark 9:23

Jesus said to him, "If there is anything I can do! Everything is possible for him who has faith!"

Matthew 14:30-31

But when he felt the wind, he was frightened, and as he began to go down, he cried out, "Lord, save me!"

Matthew 17:9

And as they were going down the mountain, Jesus warned them, saying, "Never mention to anyone what you have seen until the Son of Man is raised from the dead."

Matthew 17:17

And Jesus answered, "O you unbelieving and perverted people of the times! How long can I put up with you? Bring him here to me!"

Mark 4:31

It is like a mustard seed, which, when it is sown in the ground, is the smallest of all seeds,

Luke 1:37

For nothing is ever impossible for God."

Luke 18:27

So He said, "The things impossible for men are possible for God."

John 11:40

Jesus said to her, "Did I not promise you that if you would believe in me, you should see the glory of God?"

1 Corinthians 12:9

to another, through union with the same Spirit, faith; to another, by one and the same Spirit, power to cure the sick;

Hebrews 3:19

So we see that it was because of their unbelief that they could not be admitted to it.

Treasury of Scripture Knowledge

Summary

And Jesus said unto them, Because of your unbelief: for verily I say unto you, If ye have faith as a grain of mustard seed, ye shall say unto this mountain, Remove hence to yonder place; and it shall remove; and nothing shall be impossible unto you.

Bible References

Because

Matthew 17:17
And Jesus answered, "O you unbelieving and perverted people of the times! How long can I put up with you? Bring him here to me!"
Matthew 14:30
But when he felt the wind, he was frightened, and as he began to go down, he cried out, "Lord, save me!"
Hebrews 3:19
So we see that it was because of their unbelief that they could not be admitted to it.

A grain

Matthew 13:31
He told them this story, as follows: "The kingdom of heaven may be compared to a mustard seed which a man took and sowed in his field.
Mark 4:31
It is like a mustard seed, which, when it is sown in the ground, is the smallest of all seeds,

Nothing

Mark 9:23
Jesus said to him, "If there is anything I can do! Everything is possible for him who has faith!"
Luke 1:37
For nothing is ever impossible for God."
Luke 18:27
So He said, "The things impossible for men are possible for God."