James Boswell's uncle John was a member of a sect known as the Glasites.
A gentleman of the Chapel Royal, according to Boswell. The Chapel Royal is the official chapel of the monarch of the United Kingdom since the 12th or 13the century. He was apparently a member of the choir at St. Paul's.
Life with Boswell:
Boswell had seen him at Lord Eglinton's and met and had tee with him a few times in the summer of 1763.