The unity of the church concerned John Calvin so much that he wrote to Thomas Cranmer on April 1552: “The members of the Church being severed, the body lies bleeding. So much does this concern me, that, could I be of any service, I would not grudge to cross even ten seas, if need were, on account of it” (Letters 2:348).
Calvin took both the invisible and visible unity of the church seriously. He insisted: “The Lord esteems the communion of his church so highly that he counts as a traitor and apostate from Christianity anyone who arrogantly leaves any Christian society, provided it cherishes the true ministry of Word and sacraments” (Institutes IV.1.10). Calvin acknowledged: “Some fault may creep into the administration of either doctrine or sacraments, but this ought not to estrange us from communion with the church. For not all articles of true doctrine are of the same sort. Some are so necessary to know that they should be certain and unquestioned by all… . Such are: God is one; Christ is God and the Son of God; our salvation rests in God’s mercy; and the like. Among the churches there are other articles of doctrine disputed which do not break the unity of faith. … Does this not sufficiently indicate that a difference of opinion over these nonessential matters should in no wise be the basis of schism among Christians?” (IV.1.12).
Calvin warned: “We must not thoughtlessly forsake the church because of any petty dissension” (IV.1.12). Yet he was also wary of false forms of unity or “the false pretense of harmony. Peace is a sounding and imposing term, and whenever the Papists meet with it in Scripture they eagerly seize upon it for the purpose of raising dislike against us, as if we … were the authors of division. … Accursed then be the peace and unity by which men agree among themselves apart from God” (Commentary on a Harmony of the Evangelists, 22).
To Calvin, both faithlessness and disunity were evil. And, according to John Leith, “for Calvin faithlessness is a greater sin than disunity” (Leith, Introduction to the Reformed Tradition, 54). Nevertheless, Calvin’s commitment to unity is clear: “Let the following two points, then, stand firm. First, he who voluntarily deserts the outward communion of the church (where the Word of God is preached and the sacraments are administered) is without excuse. Secondly, neither the vices of the few nor the vices of the many in any way prevent us from duly professing our faith there in ceremonies ordained by God. For a godly conscience is not wounded by the unworthiness of another, whether pastor or layman; nor are the sacraments less pure and salutary for a holy and upright man because they are handled by unclean persons” (IV.1.19).
Likewise, in our own day, Karl Barth called Christians to unity. However, he insisted that the unity of the church is not an ideal we may strive to create. Rather it is already a reality because of who Jesus Christ is and what He has done. Thus, it is a reality we may discover only in obedience to Him, in Him, and through Him. Moreover, like Calvin, Barth was wary of false forms of unity: “The quest for unity of the Church must not be a quest for Church-unity in itself; for as such it is idle and empty. On the road to such a ‘Church-unity in itself’ we shall find that both the powers of sin and the powers of grace are against us, and against us irresistibly.”
Barth continued: “The quest for the unity of the Church must in fact be identical with the quest for Jesus Christ as the concrete Head and Lord of the Church. The blessing of unity cannot be separated from Him who
blesses, for in Him it has its source and reality, through His Word and Spirit it is revealed to us, and only in faith in Him can it become a reality among us. I repeat: Jesus Christ as the one Mediator between God and man is the oneness of the Church, is that unity within which there may be a multiplicity of communities, of gifts, of persons within one Church, while through it a multiplicity of Churches are excluded. When we confess and assert that it belongs to the Church’s commission to be one Church, we must not have in mind the idea of unity, whatever its goodness and moral beauty may be––we must have Him in our mind. … ‘Homesickness for the una sancta’ is genuine and legitimate only in so far as it is a disquietude at the fact that we have lost and forgotten Christ, and with Him have lost the unity of the Church.”
“Thus we must be on our guard, all along the line, lest the motives which stir us today lead us to a quest which looks past Him. Indeed, however rightful and urgent those motives are, we could well leave them out of our reckoning. We shall do well to realize that in themselves they are well-meaning but merely human desires, and that we can have no final certainty that they are rightful, no unanswerable claim for their fulfillment. Unless we regard them with a measure of holy indifference we are ill-placed for a quest after the unity of the Church. But we cannot leave out of our reckoning the claim urged by Jesus Christ upon us. If we listen to the voice of the Good Shepherd, then the question of the unity of the Church will most surely become for us a burning question. Then, it may be, His voice will endorse those motives of which we have spoken, with weight, necessity and imperative force; it will then be right and requisite that they should kindle us to a flame, and any indifference to them will be far from holy. From that Voice which alone can question us in tones which make ‘our hearts burn within us’ must we expect and await the ultimate answer” Karl Barth, The Church and The Churches, 18–21.
Richard Burnett, Managing Editor