A Highlander with little formal education but enormous learning and wisdom, he taught himself Latin, Greek, Hebrew, Syriac and civil and religious history. Adam Clarke once pointed him out to Jabez Bunting as 'a walking lexicon'. He was an itinerant for 50 years, chiefly in north-east Scotland. On Sundays he often preached twice in English and twice in Gaelic. John Wesley called him 'the North Star', named him in the Deed of Declaration and in 1787 ordained him for Scotland. He died on 21 July 1834 at South Shields.