All biographies of Smith Wigglesworth, a man of God, where the author had a first hand relationship with Wigglesworth have some insight of Wigglesworth that the others don't. This biography by Hacking contains a lot of insight the others don't. Mr. Hacking inlcudes notes from a week of services that Wigglesworth held in Mr. Hacking's church. These notes contain spiritual insights I have not found in any other biography or books of his sermons. Actually, in a personal letter to Mr. Hacking from Smith Wigglesworth, Wigglesworth praises him for the notes.