Answer: On two other occasions, Jesus taught His disciples the importance of increasing their faith in God. In one instance, Peter noticed that the fig tree, cursed by Jesus the day before, had withered, to which Jesus responds (Mark 11: 22-24):

22 Have faith in God. 23 For verily I say unto you, That whosoever shall say unto this mountain, Be thou removed, and be thou cast into the sea; and shall not doubt in his heart, but shall believe that those things which he saith shall come to pass; he shall have whatsoever he saith. 24 Therefore I say unto you, What things soever ye desire, when ye pray, believe that ye receive them, and ye shall have them.

In the other instance, the Apostles asked Jesus for a stronger faith (Luke 17: 5). He replies (v. 6):

“If ye had faith as a grain of mustard seed, ye might say unto this sycamine tree, Be thou plucked up by the root, and be thou planted in the sea; and it should obey you.”

The context of Matthew 17: 20 describes a man who came to Jesus, begging Him to heal his son, possessed by a demon. The man had previously taken his request to Jesus’ disciples, but they could not heal him. After Jesus successfully cured the lad, His disciples enquired as to why they had failed. Jesus’ reply is the subject of our question.

Even Small Faith Can Accomplish Much

Our Lord pinpoints the disciples’ failure as a lack of sufficient faith. He goes on to intimate that even a small amount can work wonders, just as the mustard seed produces a large tree. As to moving mountains or replanting trees in the sea, Jesus’ words suggest that there is a vast potential to a living faith which remains untapped by even the most loyal of His followers. Moses raised his staff and parted the Red Sea; Elijah prayed and ended a three-and-a-half-year drought; and Jesus by His faith overcame the world. These are exceptional manifestations of the power of belief.

It seems that it is not so much the moving of real mountains which is in view here. Rather the lesson is that the power of a confident faith in God is vastly greater than most Christians can grasp in this life. Since Jesus, the Perfect One, did not Himself hurl any real mountains into the sea during His ministry, we may assume that this particular demonstration was not in keeping with God’s will at the time.

From the figurative point of view, the “mountains” may be those difficulties or obstructions along our Christian course. By exercising a steady trust in God’s ability to see us through, and going forward in the Lord’s strength, we are to serve Him and develop the Christian graces, overcoming difficulties otherwise impossible. Surely, we can always exercise more faith.

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