On May 28, 1787 the delegates heard and approved the rules which governed the Convention. These sound very much like Robert’s Rules of Order, which were published in the mid-1800s.
I like this one:
A member may be called to order by any other member, as well as by the President; and may be allowed to explain his conduct, or expressions supposed to be reprehensible. And all questions of order shall be decided by the President, without appeal or debate. (p. 57)
George Washington had the final say to decide if a member was unruly.
I note that the Convention did not open in prayer nor did they appeal to any religious basis for their tasks.
Source for notes on the entire Convention; notes for May 28.