Doubt not (mh diakriqhte). First aorist passive subjunctive, second-class condition. To be divided in mind, to waver, to doubt, the opposite of "faith" (pistin), trust, confidence. What is done to the fig tree (to th sukh). The Greek means "the matter of the fig tree," as if a slight matter in comparison with this mountain (twi orei toutwi). Removing a mountain is a bigger task than blighting a fig tree. "The cursing of the fig-tree has always been regarded as of symbolic import, the tree being in Christ's mind an emblem of the Jewish people, with a great show of religion and no fruit of real godliness. This hypothesis is very credible" (Bruce). Plummer follows Zahn in referring it to the Holy City. Certainly "this mountain" is a parable and one already reported in Matthew 17:20 (cf. sycamine tree in Luke 17:6 ). Cf. Zechariah 4:7 .