Do ye not know... ? — The knowledge which they possessed of the great future which was in store for the Church of Christ was the strongest argument against the humiliating degradation to which their conduct was subjecting it.
The saints shall judge the world. — The Apostle here claims for all Christians the glorious prerogative which Christ had Himself promised to His immediate personal followers (Matthew 19:28; Luke 22:30). Bearing in mind the deep conviction of the early Church that the second personal advent of Christ was near at hand, we may take these words as referring primarily to the conquest of the world by Christianity, which has since been accomplished, though by slower and more spiritual processes than were then anticipated, and indirectly to that final triumph of Christ and His body, the Church, of which every success here on earth is at once the type and the pledge.
To judge the smallest matters. — Better, to pronounce the most trivial judgments, as compared with the great judgments which you shall pronounce hereafter. The nature of the things which form the subject of those judgments is explained in the following verse.