George Washington's REAL Prayerbook:

This is one piece of evidence Peter Lillback harps on to try and prove GW's orthodox Christianity. These were not "prayers written in GW's hand" like the debunked Daily Sacrifice supposedly was. Rather, it is the standard Anglican Prayer book (I believe the 1769 version was the most recently revised edition when GW wrote the following). From INVOICE OF GOODS TO BE SHIPD BY ROBERT CARY & CO. FOR THE USE OF GEO. WASHINGTON, POTOMACK RIVER, VIRGINIA, VIZ. July 18, 1771.

A Prayr. Book with the new Version of Psalms and good plain type, covd. with red Moroco., to be 7 Inchs. long 4� wide, and as thin as possible for the greatr. ease of caryg. in the Pocket.

Lillback's argument is this proves GW was an orthodox Christian because the contents of the prayer book taught orthodox Christianity. But James H. Hutson's page from the Library of Congress illustrates the problem with such reductive conclusions:

The American Revolution inflicted deeper wounds on the Church of England in America than on any other denomination because the King of England was the head of the church. Anglican priests, at their ordination, swore allegiance to the King. The Book of Common Prayer offered prayers for the monarch, beseeching God "to be his defender and keeper, giving him victory over all his enemies," who in 1776 were American soldiers as well as friends and neighbors of American Anglicans. Loyalty to the church and to its head could be construed as treason to the American cause. Patriotic American Anglicans, loathe to discard so fundamental a component of their faith as The Book of Common Prayer, revised it to conform to the political realities.

That is, the contents of the Book of Common Prayer were Tory and High Church (demanding loyalty to the Crown). It's really strange that so many Anglicans turned out to be Whigs. They rebelled against, not only England, but what their church taught. One wonders why there wasn't a massive exodus among them to other churches. And the answer is they valued their attachment to Anglicanism for social reasons. There were, at least in high places, more than a nominal number of deistic and unitarian minded Anglicans who were part of the church for club membership reasons but didn't believe in its official doctrines.