His book "Time for a Change: Reconfiguring Religion, State and Society" draws on the resources of the Baptist ecclesiology of "covenantal voluntarism" and on Baptist advocacy for religious liberty as models for the increasingly diverse religious, social and political landscape of the United Kingdom.
After briefly recounting the history of England's established Church, Weller describes the Baptist struggle for religious liberty in two clear and succinct chapters. One chapter on the struggle in England and another on the struggle in America.
Then he documents the burgeoning religious diversity within the UK, summarizes his previously published research on religious discrimination toward minority faiths in England and Ireland, and discusses more fully the need for a change toward a more Baptist model for church-state relations.
Here's a quotation from Weller's discussion of the Baptist vision for society:
For the Baptist vision, the promotion of religious freedom has been, and is, a theologically grounded conviction and practice. While the promotion of religious liberty has opened up possibilities for religious toleration, the commitment to religious liberty is basically different from toleration. While in many social contexts toleration represents a significant advance, it continues to reserve to itself the right not to recognize other groups, and in fact, sometimes exercises this option. Toleration implies retention of imbalances in religious power and tends to be based upon political pragmatism rather than theological principle. In addition, as the Mennonite writer Harold Bender pointed out, it can be the product of religious indifferentism:Reading Dr. Weller's book about problems with the established church in England might prove sobering for those "values-voter" Baptists in the United States who, drunk with the wine of political power, are jettisoning the Baptist legacy regarding religious liberty and working to establish religion in America.It is a deeply disturbing fact that the victory for toleration in the seventeenth, eighteenth, and nineteenth centuries was to a large degree due not to the will of the dominant Christian Churches, Catholic or Protestant, but to the will of rulers exhausted by religious wars and determined to find a basis for peace in the European community which would transcend the warring religious parties; or to the growing rationalism, secularism and materialism of the politically ever more powerful upper middle class, which placed religion low in the scale of cultural values and, in the words of Frederick the Great, was quite willing to have everyone 'saved after his own fashion' -- or in the words of Theodore Beza a century and a half earlier, 'to go to hell in his own fashion.'The strength of the Baptist vision of religious liberty is that it is not a product of religious indifference. Rather, it is theologically based. As a contemporary theological resource, the Baptist tradition's commitment to religious freedom thus provides a basis for Christian acceptance of the fact of religious plurality understood as a theological imperative. This contrasts with the approach of granting recognition of such plurality merely as a grudging concession consequent upon increasing pluralization of the social context and the privatization of religion. The Baptist vision of a theologically grounded commitment to religious freedom enables the possibility of maintaining distinctive and passionately held religious convictions alongside a deep concern for the promotion of the religious rights of others.