The means by which this unity was to be maintained was chiefly the prevalence of the Christian affections in the hearts of believers--the presence and power of that mind of Christ, of which more must be said in connection with the following chapter. Certainly the Apostle regards this as, at any rate, the radical security for unity in life and work, and without it he does not suppose the unity for which he cares can exist at all. In this connection it is worth observing that the unity he is thinking of is chiefly that which should bind together the members of those little communities which were rising up in various places under his ministry. It is the harmony of those whose lot is cast in the same place, who can influence one another, whose plain business it was to confess Christ together. Wider unity was supposed indeed, and was rejoiced in; but the maintenance of it had not yet become so much a practical question. This continued to be the case for some time after the Apostolic period. Men were anxious to hold each local congregation together, and to avert local splits and quarrels. If that were done, it seemed as though nothing further were urgently needed. Yet the same principles establish the unity of the visible Church throughout the world, and indicate the discharge of the duties which are necessary in order to the expression of it. Christians differ indeed among themselves upon the question how far the Church has received organic institutions fitted to give expression or embodiment to her unity; and diversity of judgment on that point is not likely soon to be removed. For the rest the main thing to observe is that Christ's Church _is_ one, in root and principle. This applies not only to the Church invisible, but to the Church visible too. Only the latter, as she falls short in all service and attainment, falls short also in expressing her own unity and in performing the duties connected with it. On the one hand they err who think that because the state of the visible Church is marred by divisions, therefore unity in her case is a dream, and that the unity of the Church invisible is alone to be asserted. On the other hand they err who, on much the same grounds, conclude that only one of the organised communions can possess the nature and attributes of the visible Church of Christ. The visible Churches are imperfect in their unity as they are in their holiness. In both respects their state is neither to be absolutely condemned nor to be absolutely approved. And no one of them is entitled to throw upon the rest all the blame of the measure of disunion. Any one that does so becomes a principal fomenter of disunion.