THE Labour Party, according to Morgan Phillips, Labour's general secretary from 1944 to 1961, owes more to Methodism than to Marxism. An ethos of moderation, self-improvement, and, above all, the discipline of the Methodist class meeting have all had their effects on the Labour movement.

Methodist class meetings were about mutual support and solidarity in the struggle of faith. It was perhaps no accident that the trade- union movement adopted a vocabulary drawn from eccesiology: local branches are "chapels", and their leaders are Fathers and Mothers.

Anglican thinkers such as F. D. Maurice, B. F. Westcott, and William Temple recognised within the Labour movement a resonance with the Pauline and patristic vision of corporate salvation in Christ. For them and their successors, solidarity has always spoken of Christ's headship more truthfully than individualistic piety.

Ed Miliband's attempt to stop the trade unions' automatically affiliating their members to the Labour Party represents a more radical break with this strand of the movement's past than is sometimes realised. In the press, the issue is treated cynically; if he succeeds in pushing though the change, how will Labour cope financially?

The deeper issue, perhaps, is what would happen to the implicit theology of British Socialism. That theology sees the Labour movement as a crusade, and the unions as the agents of justice for working people. To join a union is to subsume one's individual struggle for dignity and freedom into a shared struggle. The transfer of funds to a political party is a symbol of the transfer of the private self to the corporate body.

It doesn't matter that a quarter of union members actually vote Conservative. The money that goes to Labour through their union membership supports the sacred cause. To lose this link, however discredited it now seems to some, is to strike at the party's moral heart. It would make Labour what un-sympathetic critics say that it is, a party representing the interests of a particular section of society, a sectarian chapel rather than a broad church.

Those who support reform believe that the old theology is no longer persuasive, and that what was once morally compelling is now morally dubious. Labour's appeal must be broader and less sectarian. Tony Blair understood this well, and Mr Miliband appears to be getting there. Paradoxically, the last politician really to understand the old theology of Trades Unionism was Margaret Thatcher. She despised it in its union manifestation, though she was not far from it herself in her more sectarian moments.