The British Whig Tradition:

For 2007, expect me to further research the radical British Whigs of the English Civil War and Commonwealth period and pay special attention to how they viewed Church/State matters and to their personal religious beliefs. The most prominent historians in the academy, notably Bernard Bailyn and Gordon Wood argue this group most greatly influenced our Founders. Bailyn notes that Founding principles synthesized four or five different school of thought: Biblical/Christian (especially New England Covenant theology), Pagan/Greco Roman, Common Law/Rights of Englishmen, and Enlightenment/natural rights of man. Arguably the British Whig principles were part of the broader Enlightenment tradition. Though some of them did predate the Enlightenment. So perhaps they deserve their own fifth and distinct category (Bailyn hedges between these four and five categories). But it was this last category or two categories -- Enlightenment and English Whiggery -- that dominated and was the lens through which all sources were viewed.

The English Whigs were not part of the common law tradition, because (as I understand) common law was 1) much older, and 2) incorporated a Blackstonian Tory approach to absolute parliamentary sovereignty that was incompatible with such Whig radicalism. Blackstone said of Parliament:

It can, in short, do every thing that is not naturally impossible; and therefore some have not scrupled to call it's power, by a figure rather too bold, the omnipotence of parliament. True it is, that what they do, no authority upon earth can undo.

As Gary North writes, "Blackstone was wrong: beginning eleven years later, the American colonies undid a lot of what Parliament had done."

These Whig thinkers were more likely to invoke the natural rights of man, not simply the common law rights of Englishmen and hence fit better within the Enlightenment tradition. However, as noted, some of them predated the Enlightenment -- for instance, John Milton. See this article noting Milton's pro-liberty influence and connecting it to Milton's Puritan Christianity. Though these Whigs weren't entirely monolithic in their thinking, from what I've been able to observe (and what I am going to try to document) a disproportionate number of them asserted the primacy of natural religion over revealed religion and denied the Trinity. And they were more likely to use terms like Separation of Church and State and, as libertarians, were on the cutting edge of religious liberty issues.

Most of them like John Locke arguably belong to both the "Enlightenment" and "Whig" categories.

Anyway, besides Locke and Milton, they include: Joseph Priestly, Richard Price, James Burgh, Algernon Sidney, Thomas Gordon, John Trenchard, Viscount Bolingbroke, Shaftsbury, Benjamin Hoadly, and John Cartwright. There are others as well. Priestly and Burgh actually used the term "Separation of Church and State" before Jefferson. Indeed, even though Roger Williams, founder the Rhode Island colony, coined the term, it's unlikely that Jefferson learned the phrase from or had even read Williams. Jefferson likely learned it from James Burgh. See also this link from Kenneth R. Gregg on Burgh and Separation.