Of all the instruments associated with the blues, the guitar is predominant. And of all the instruments associated with popular culture, the impact of the blues on the guitar – be it in the hands of Jimi Hendrix, Eric Clapton, or Kurt Cobain – is incalculable. But where did it all start? Can you really make a link between the psychedelic explosions of a pop icon (albeit one who would regularly include blues standards in his repertoire) and a lay preacher from the Mississippi Delta like Blind Willie Johnson? And what about the link between the sacred and the secular forms of the music? Today we tend to see blues and gospel as two distinct genres or, as is the case in today's commercially driven world, two separate markets. As we shall see, it wasn't always thus. The two branches share the same roots.

“You know, the blues come out of the field, baby,” Sam “Lightning” Hopkins told Sam Charters in 1964. “That's when you bend down, pickin' that cotton and sing ‘Oh Lord, please help me’.” Always a secular performer, he was nonetheless at pains to acknowledge the important role of religion, underlining the way in which the line between blues and gospel is often blurred. “The blues is a lot like church … when a preacher's up there preachin' the Bible, he's honest to God tryin' to get you to understand these things. Well, singin' the blues is the same thing” (Charters 1965: 375).