This is a hand-finished relief etching, printed on paper from a copper plate. The broken texture visible along the light grey outline of God's right arm was produced as the printing plate was lifted off the paper.
Blake's figure of God resembles Urizen, a tyrannical law-maker in Blake's own mythology. God holds his sceptre in his right hand here but, because images are reversed during printing, Blake would have had to show it in God's left hand on the copper printing plate.