In one of his writings on the doctrine of the church in relation to ecclesial life in seventeenth-century England, John Owen makes
what I think are a number of incisive and helpful comments on schism and unity. As a Congregationalist, Owen was susceptible to accusations of schism and divisiveness, but he suggests that a poor conception of church unity and a misguided zeal for that conception underlie the charges against the Nonconformists.
For Owen, the unity of the church is fundamentally spiritual, a function of believers being joined to Christ their head by faith. However, Owen argues, in his day many conceived of unity in terms of (humanly devised) external uniformity of order and liturgy and then sought to impose that uniformity on all churches in the land. This misconception generated charges of schism against Owen and his Puritan comrades and, intriguingly, was the principal cause of ecclesial disunity. Externalize unity and impose that external unity on others and those of a different ecclesiological persuasion will (justifiably) resist this. Hence those who are overzealous for unity are also the chief culprits in schism. Though Owen has in mind especially the Anglican leaders of the time, he mentions Rome as an egregious example of supplanting spiritual unity with an external unity ‘of their own invention’ (Works of Owen, 15:111-12):