His "report on silence within Christian history" grew out of a set of Gifford lectures, an annual endowed series on "natural theology" presented at Scottish universities. He's not the sort to be overawed by this academic honor; here's a smidgen of his introduction to Silence.
And so he has given us a great deal more. I'll just be highlighting a few of his topics that I found fascinating.
In a section he calls "Silences for Survival," he discusses the repeated reality that religion forced some people to make themselves invisible to preserve their lives. The Reformer John Calvin called such people
MacCullogh's catalog of such people includes Jews and Muslims forcibly converted by inquisitorial Spain, reformation radicals who found themselves in principalities with hostile rulers with different religious allegiances, and, interestingly, many of the leaders in constructing what became the established Church of England.
The history of Christianity is full of "things casually or deliberately forgotten, or left unsaid..." MacCulloch reminded his listeners that churches used to routinely deny participation in communion to women who were menstruating -- in sacramental Lutheranism and Anglo-Catholicism as late as the 1950s. Yet somehow this purity practice has simply disappeared from history. In general women's roles in the Churches have been the occasion of many silences.
MacCulloch grapples with what we moderns might consider one of the Churches' greatest sins and he goes to the heart of why change here proved so intractable.
Because varieties of Christianity that arose out of the European Reformation represented a backlash against the entitled and uninspiring culture of medieval Catholic monasticism, their offspring which include mainline Protestants, Evangelicals, and even modern Catholicism, strike MacCullogh as "Word-centred" but also simply "noisy." Many Christians in other places and times, including our own European ancestors, found silence a valid and valued approach to the divine. Perhaps silence might be part of what the contemporary "spiritual but not religious" are looking for?