He said to them, “Because of your little faith. For truly, I say to you, if you have faith like 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 for you.”
We have here the miraculous cure of a child that was lunatic and vexed with a devil. Observe, I. A melancholy representation of the case of this child, made to Christ by the afflicted father. This was immediately upon his coming down from the mountain where he was transfigured. Note, Christ's glories do not make him unmindful of us and of our wants and miseries.
Commenting on Matthew 17:14-21
And Jesus said unto them, because of your unbelief,.... The Arabic and Ethiopic versions read, "because of your little faith", or "the smallness of your faith"; and so does one Greek manuscript; and which is what is doubtless meant by their unbelief; for they were not altogether destitute of faith, but their faith was very low, and their unbelief very great.
Verse 20. As a grain of mustard seed. . The mustard seed was the smallest of all Seeds. It has been supposed by some, therefore, that he meant to say, if ye have the smallest or feeblest faith that is genuine, ye can do all things. The mustard seed produced the largest of all herbs.