Excerpt: "Robert Barclay is most widely known for writing the Apology for the True Christian Divinity (1676 in Latin; 1678 in English). But this was not his first important Quaker work. A Catechism and Con fission of Faith was written in 1673, about seven years after his "convincement" of the truth, and when he was only 24 years old."
Anderson, Paul N., "Foreword to A Catechism and Confession of Faith" (2001). Faculty Publications - College of Christian Studies. 347.