Jesus' blood never failed me yet

My brother came up for his tea tonight and, somehow or other, we got onto a piece of music I heard - by chance - years ago. The piece of music was Jesus' blood never failed me yet  by Gavin Bryars.

It's a recording from a documentary and in it a Down-and-out spontaneously sings the refrain Jesus' blood never failed me yet / it's one thing I know / for he loves me so over and over. It begins with a simple singing and repeats itself and gradually builds and swells around these same three lines.
It starts off plaintive, slightly comical; then a bit annoying until something sublime happens and it swells and gathers this simple human declaration of faith in something greater than itself. It becomes the truth, the ineffable speak of that great billowing life inside of us all regardless of our exterior conditions.

My brother reacted in a similar way that I did to it. That it was the wailing of an alcoholic. Yet that is exactly the beauty of it. Jesus' blood: is the tramp's faith in the spiritual solace of Jesus, or in the 'Jesus' blood' that is wine ? It is amibiguous and moving. We are all struggling with the human.
Down-and-outs are perhaps closer to the momentary struggle, the blood and guts of it all. They are off of the carousel of the workday week. The are sodden with defeat and struggle and a desire to escape it for a while. They are prostrate before the modern world. For me, that is the power in this piece of music. When we weaken to whom do we turn?
Over and over goes the warbling refrain, and we hear certainty slip into doubt into puzzlement into doubt into certainty into submission. The only thing you get to keep is what you give away.