David and John) and four daughters (Patience, Catherine, Christian and Jean).

The essential view which Barclay maintained was that all people can be illuminated by the Inward Light of Christ "which is the author of the Scriptures and will lead them into all truth". His works have often been reprinted. He was an ardent theological student, a man of warm feelings and considerable mental powers, and he soon came prominently forward as the leading apologist of the new doctrine, winning his spurs in a controversy