Now that the Church is broken into pieces, perhaps the first step towards a restoration of true unity is to recognise that there may be real union without unity of external organization. In other words, it is quite possible that Churches which have individually a separate corporate existence--say the Presbyterian, Independent, and Episcopalian Churches--may be one in the New Testament sense. The human race is one; but this unity admits of numberless varieties and diversities in appearance, in colour, in language, and of endless subordinate divisions into races, tribes, and nations. So the Church may be truly one, one in the sense intended by our Lord, one in the _unity of the Spirit_ and the bond of peace, though there continue to be various divisions and sects. It may very well be argued that, constituted as human nature is, the Church, like every other society or institution, will be the better of a competing, if not an opposing, rival; that schism, divisions, sects, are necessary evils; that truth will be more thoroughly investigated, discipline more diligently and justly maintained, useful activities more vigorously engaged in, if there be rival Churches than if there be one. And it is certainly true that, so far as man can foresee, there is no possibility, not to say prospect, of the Church of Christ becoming one vast visible organization. Oneness in that sense is prevented by the very same obstacles that hinder all States and governments on earth from being merged into one great kingdom. But as amidst all diversities of government and customs it is the duty of States to remember and maintain their common brotherhood and abstain from tyranny, oppression, and war, so it is the duty of Churches, however separate in creed or form of government, to maintain and exhibit their unity. If the sects of the Church will frankly and cordially recognise one another as parts of the same whole, if they will exhibit their relationship by combining in good works, by an interchange of ecclesiastical civilities, by aiding one another when aid is needed, this is, I conceive, real union. Certainly Churches which see it to be their duty to maintain a separate existence ought to be equally careful to maintain a real unity with all other Churches.
Again, it is to be borne in mind that there may be real union without unity in creed. As Churches may be truly one though, for the sake of convenience or of some conscientious scruple, they maintain a separate existence, so the unity required in the New Testament is not uniformity of belief in respect to all articles of faith. This uniformity is desirable; it is desirable that all men know the truth. Paul here and elsewhere entreats his readers to endeavour to agree and be of one mind. It is quite true that the Church has gained much by difference of opinion. It is true that were all men to be agreed there might be a danger of truth becoming lifeless and forgotten for want of the stimulus it derives from assault, and discussion, and cross-questioning. It is undoubtedly the fact that doctrine has been ascertained and developed precisely in proportion and in answer to the errors and mistakes of heretics; and were all assault and opposition even now to cease, there might be some danger of a lifeless treatment of truth ensuing. And yet no one can desire that men be in error; no one can wish heresies to multiply that the Church may be stimulated. A visitation of cholera may result in cleanliness and carefulness, but no one desires that cholera may come. Opposition in Parliament is an acknowledged service to the country, yet each party desires that its sentiments become universal. So, too, notwithstanding every good result which may flow from diversity of opinion regarding Divine truth, agreement and unanimity are what all should aim at. We may even see reason to believe that men will never all think alike; we may think that it is not in the nature of things that men of diverse natural disposition, diverse experience and upbringing, should think the same thing; if it is true, as a great thinker has said, that "our system of thought is very often only the history of our heart," then the effort to bring men to precise uniformity of thought is hopeless: and yet this effort must be made. No man who believes he has found the truth can forbear disseminating it to the utmost of his ability. If his favourite views are opposed in conversation, he does what he can to convince and make converts of his antagonists. There is truth, there is a right and a wrong, and it is not all the same whether we know the truth or are in error; and doctrine is simply truth expressed: and though the whole truth may not be expressed, yet even this partial expression of it may be much safer and nearer what we ought to believe than some current denial of the truth. Paul wishes people to believe certain things, not as if then they would be fully enlightened, but because so far they will be enlightened and so far defended against error.