The real difficulty here lies in the eighth verse, where the Apostle explains, apparently, why he acts on the principle just stated. "I pray this prayer for you," he seems to say, "and I am content to pass as a reprobate, while you do that which is honourable; for I can do nothing against the truth, but for the truth." What is the connexion of ideas alluded to by this "for"? Some of the commentators give up the question in despair; others only remind one of the French pastor who said to some one who preached on Romans: "Saint Paul est déjà fort difficile et ... vous veniez après." As far as one can make out, he seems to say: "I act on this principle because it is the one which furthers the truth, and therefore is obligatory upon me; I am not able to act on one which would injure or prejudice the truth." The truth, in this interpretation, would be synonymous, as it often is in the New Testament, with the Gospel. Paul is incapable of acting in a way that would check the Gospel, and its influence over men; he has no choice but to act in its interest; and therefore he is content to let the Corinthians think what they please of him, provided his prayer is answered, and they do no evil, but rather that which is good before God. For this is what the Gospel requires. "Content," indeed, is not a strong enough word. "We _rejoice_," he says in ver. 9, "when we are weak, and you are strong: this we also pray for, even your perfecting." "Perfecting" is perhaps as good a word as can be got for κατάρτισις: it denotes the putting right of all that is defective or amiss.
It is in favour of this interpretation of the eighth verse that the reason seems at first out of proportion to the conclusion. With an idealist like Paul it is always so. He appeals to the loftiest motives to influence the lowliest actions,--to faith in the Incarnation, as a motive to generosity--to faith in the Resurrection Life, as a motive to patient continuance in well-doing--to faith in the heavenly citizenship of believers, as a motive to separation from the licentious. In the same way he appeals here to a universal moral rule to explain his conduct in a particular case. His principle everywhere is, not to act in prejudice of (κατά) the Gospel, but in furtherance of it (ὑπέρ); he has strength available for this last purpose, but none at all for the former. It is the rule on which every minister of Christ should always act; and if the line of conduct which it pointed out sometimes led men to disregard their own reputation, provided the Gospel was having free course, the very strangeness of such a result might turn to the furtherance of the truth. It is by-ends that explain nine-tenths of spiritual inefficiency; singleness of mind like this would save us our perplexities and our failures alike.
It is because he has an interest like this in the Corinthians that Paul writes as he has done while absent from Corinth. He does not wish, when he comes among them, to proceed with severity. The power the Lord gave him would entitle him to do so; yet he remembers that this power was given him, as he has remarked already (x. 8), for building up, and not for casting down. Even casting down with a view to building up on a better basis was a less natural, if sometimes a necessary, exercise of it; and he hopes that the severity of his words will lead, even before his coming, to such voluntary action on the part of the Church as will spare him severity in deed.
This is practically the end of the letter, and the mind involuntarily goes back to the beginning. We see now the three great divisions of it plainly before our eyes. In _the first seven chapters_ Paul writes under the general impression of the good news Titus has brought from Corinth. It has made him glad, and he writes gladly. The one case that he had been concerned about has been disposed of in a way that he can consider satisfactory; the Church, in the majority of its members, has acted well in the matter. _The eighth and ninth chapters_ are a digression: they are concerned solely with the collection for the poor at Jerusalem, and Paul inserts them where they stand perhaps because the transition was easy from his joy over the change at Corinth to his joy over the liberality of the Macedonians. In _chaps, x. 1-xiii._ 10 he evidently writes in a very different strain. The Church, as a whole, has returned to its allegiance, especially on the moral question at issue; but there are Jewish interlopers in it, subverting the Gospel, and reconverting Paul's converts to their own illiberal faith; and there are also, as it would appear, numbers of sensual people who have not yet renounced the vilest sins. It is these two sets of persons who are in view in the last four chapters; and it is the utter inconsistency of Judaic nationalism on the one hand, and Corinthian licence on the other, with the spiritual Gospel of the Son of God, that explains the seventy of his tone. "The truth" is at stake--the truth for which he has suffered all that he recounts in chap. xi.--and no vehemence is too passionate for the occasion. Yet love controls it all, and he speaks severely that he may not have to act severely; he writes these things that, if possible, he may be spared the pain of saying them.