On 13 September 1644 Vane acted with St John and Cromwell in the Commons to set up a "Grand Committee for the Accommodation", designed to find a compromise on religious issues dividing the Westminster Assembly. He sought in its debate to identify loopholes for religious tolerance on behalf of the Independents. This exposed Vane's opposition to Presbyterianism, and created a rift between the pro-war Independents, led by Vane and Cromwell, and the pro-peace Scots and other supporters of Presbyterianism. The latter included the Earl of Essex, whose failures in the west of England reduced popular support for his cause, even as the military success of Cromwell at Marston Moor raised his profile. Robert Baillie, on the realisation that the Parliamentary Independents, despite previous claims of support by Vane, were not on the side of the Scots, wrote "Sir Henry Vane and The Solicitor John... without any regard for us, who have saved their nation and brought their two persons to the height of power now they enjoy and use to our prejudice".