Robert Barclay (1648–1690) was a Scottish preacher, Quaker theologian, and apologist whose writings, including his influential Catechism and Confession of Faith, provided a foundational theological framework for the Religious Society of Friends during its early development. Born on December 23, 1648, in Gordonstoun, Morayshire, Scotland, he was the eldest son of David Barclay, a military officer who later embraced Quakerism, and Katherine Gordon, daughter of Sir Robert Gordon of Gordonstoun. Educated at the Scots College in Paris under his uncle’s direction, Barclay excelled in Latin and theology but returned to Scotland in 1664 amid family concerns about Roman Catholic influence. Converted to Quakerism in 1667 at age 19 through the ministry of George Keith and William Penn—following his father’s convincement in 1666—he adopted the movement’s focus on the Inner Light as divine revelation. In 1669, he married Christian Mollison, a Quaker merchant’s daughter from Aberdeen, and they had seven children who survived infancy. Barclay’s preaching career began soon after his conversion, as he traveled across Scotland and England to proclaim Quaker principles, often enduring persecution under the Conventicle Acts, including imprisonment in Aberdeen. His most enduring legacy stems from his writings, notably An Apology for the True Christian Divinity (1676 in Latin, 1678 in English), a systematic defense of Quaker beliefs, and Catechism and Confession of Faith (1673), which offered a concise exposition of Quaker doctrine through scriptural questions and answers, reinforcing the movement’s rejection of formal creeds in favor of personal experience of God. Appointed Governor of East Jersey in 1682—though he never resided there—he leveraged his influence to promote religious liberty. Known for his gentle spirit and intellectual clarity, Barclay preached at Quaker meetings and engaged in debates, shaping the Society of Friends’ identity.