And Jesus said to them, “Because of your little faith. For truly I tell you, if you have faith the size of a mustard seed, you will say to this mountain, ‘Move from here to there,’ and it will move, and nothing will be impossible for you.”
Jesus explains to the disciples that the reason for their inability was not a lack of authority, but weak, ineffective faith. He uses the metaphor of a “mustard seed” to emphasize that even small, yet living, trusting, full faith has power. The expression “move the mountain” means to overcome obstacles that seem impossible to a person, when you rely on God. This word from Jesus is not a promise of magical power, but confidence in God’s power, which will act if the faith is real.