The last paragraph of Washington’s first inaugural address solicit’s God’s blessing on the new nation, albeit much more wordily than the now-usual version:
Having thus imported to you my sentiments, as they have been awakened by the occasion which brings us together, I shall take my present leave; but not without resorting once more to the benign parent of the human race, in humble supplication that since he has been pleased to favour the American people, with opportunities for deliberating in perfect tranquility, and dispositions for deciding with unparellelled unanimity on a form of Government, for the security of their Union, and the advancement of their happiness; so his divine blessing may be equally conspicuous in the enlarged views, the temperate consultations, and the wise measures on which the success of this Government must depend.
OTOH, his extremely short 2nd inaugural address made no mention of God, and I don’t think there’s anything similar in his farewell address.
Adams’ inaugural, and both of Jefferson’s, ended with elaborate invocations of God’s blessing on the country. There’s a web page devoted to presidential inaugural speeches at http://www.yale.edu/lawweb/avalon/presiden/inaug/inaug.htm
which you could use to research the question. Oddly, they don’t have Dubya’s second, but every inaugural address since Reagan has ended with either “God bless you” or “God bless America” or some close variant.