One of John Wesley's first itinerants, he was born at Skircoat Green, Halifax, possibly on 17 March 1726. The story of his conversion under the preaching of Henry Venn, despite finding its way into the Oxford DNB, is based on confusion with another person of the same name, associated with The Square Chapel, Halifax. (Venn's ministry in Yorkshire did not begin until 1759.) Kershaw had joined the itinerancy by 1749 and remained active intermittently until 1767. He withdrew in 1752, then returned in 1757. As early as 1747 he appears to have organised a class-meeting in County Armagh and may deserve the accolade of having been the first Methodist to preach in Ireland(preceding Thomas *Williams). Later he was John Wesleys travelling companion on some of his journeys in the north and in Scotland. He was in Edinburgh in 1763 and again in 1765. In 1765 and 1766 he was listed in the Yarm Circuit. He then settled at Stokesley, near Yarm, and from 1770 on at Gainsborough.
He took up medicine and was referred to by Wesley himself as Dr Kershaw. As a vendor of medicines, including Kershaws Balsam, he is described as riding through the countryside 'in his own vehicle, preaching in the villages and giving medical advice to the labouring classes, thus manifesting a laudable concern both for the bodies and souls of the people'. He was gifted as a preacher and writer, but Atmore's judgment was that his unstable character (which some even labelled madness) limited his usefulness. In 1764 he wrote a reply to the preface written by Dr John Erskine for the republication of James Hervey's Eleven Letters to John Wesley. In 1780 he published a series of dialogues on parts of the Book of Revelation. In the same year his poem The Methodist; attempted in Plain Metre, a sort of Wesleyan epic which has been described as the first biography of Wesley, caused some concern as bringing reproach on the Methodists and prompted Wesley at the 1781 Conference to impose a censorship over the preachers' publications. James Kershaw died at Ashby de la Zouche in 1797.
His son John Kershaw (1766-1855; e.m.1788) served as Book Steward from 1823 to 1827. Despite finding himself unequal to the task, he was described by Thomas Jackson as 'a most amiable, friendly and upright man'. His article in the Methodist Magazine in 1817, suggesting the desirability of local Methodist histories, is said to have influenced James Everett. He died at Stoke Newington in 1855. Arthur Kershaw ( ? -1824), probably another son, itinerated briefly during 1774/75 before moving on to a career as a translator and journalist.
'My connexion with the literary establishment of Methodism brought me into constant intercourse with Mr. Kershaw, who then sustained the office of Book-Steward; and whom I ever found to be a most amiable, friendly and upright man. His preaching I greatly admired It was no dishonour to him that he felt himself inadequate, at his time of life, to the successful management of a large and complicated business-concern, alien from the habits to which he had been trained; and that he therefore resigned a situation which ought never to have been forced upon him. My recollections of him are all of a pleasurable kind. In his countenance and general appearance, it was often observed, that he bore a striking resemblance to the Duke of Kent. I have a distinct remembrance of Mr. Kershaw's father, whom I heard preach in the parlour of a farmhouse in my boyhood. He was a fine-looking man, and was known in Yorkshire by the name of "Dr. Kershaw". He travelled through the country in his own vehicle, preaching in villages, and giving medical advice to the labouring classes; thus manifesting a laudable concern both for the bodies and the souls of the people '
Thomas Jackson, Recollections of my own Life and Times (1873) p.220