Matthew 17:20

20. Because of your unbelief During the absence of their Lord, the disciples seem to have become as it were secularized. See introduction to the section. Faith as a grain of mustard seed That is, in size; in contrast with the size of the mountain it is able to remove. This mountain This faith, be it remembered, supposes a concurrence between God and man.

On the part of God a mission or duty assigned to the man, for which the power of faith is granted; and without this, the true faith is impossible. On the part of man there must be exercised all the granted faith-power, by which he puts forth the act, or pursues the course which is opened in the way of duty before him. When these two things combine, it is literally true that anything is possible. If the man’s mission be to remove the Andes into the Pacific it can be done. If there be no duty to it, there can be no true faith for it; and the attempt to do it would not be faith but rash self-will. God gives no man faith wherewith to play miraculous pranks. On the other hand, if there be the duty and the God-given power of faith, and yet it be not exercised with the full strength of heart and the firm trust in God which knows the impossibility will be done, no miracle shall follow. This the disciples had not, even to a mustard seed’s amount; and a mustard seed’s amount could have as easily accomplished its mission as my hand moves a pen. There doubtless lives many a Christian now with faith sufficient to remove real material mountains, if God had any such work for him to do. Yet it may be safely presumed that our Lord used the word mountain as well as the mustard seed by way of figure. He may have used it as Isaiah 40:4, prophesies that “every valley shall be exalted, and every mountain shall be brought low.” Or as Zechariah 4:7, declares that the “great mountain shall disappear before Zerubbabel.”