'Little Faith' in the Bible

Now if God so clothes the grass of the field, which today is, and tomorrow is thrown into the oven, will he not much more clothe you, O you of little faith?

And he said to them, "Why are you afraid, O you of little faith?" Then he rose and rebuked the winds and the sea, and there was a great calm.

Jesus immediately reached out his hand and caught him, and said to him, "O you of little faith, why did you doubt?"

But Jesus, aware of this, said, "O men of little faith, why do you discuss among yourselves the fact that you have no bread?

So he said to them, "Because of your little faith. For truly, I say to you, if you have faith as 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 to you."