This phrase, out of context, could mean many things Absent of the original context of its presentation or creation the author may or may not intend to blur the intended message
"surly" is an adjective It has many meanings: (A) menacing or threatening in appearance eg surly weather (B) arrogant, imperious (C) irritably sullen (D) crabbed ie churlish in mood or manner
For example: (1) I left my body, ie I died = I slipped the + (any adjective) + bonds of Earth (2) I cleaned my body after being in the mud, after being heavily soiled by earth = I got rid of the earth stuck to my body = I slipped (= I escaped) the + (any adjective) + bonds (connections; restraints) of Earth (3)I slipped the + (any adjective) + bonds of earth = I escaped (same adjective) earthen restraints = I let go of (same adjective) earthen attachments
"slipped the surly bonds of earth to touch the face of God"
Leaving the earth should be done against the force of gravity. But, I don't know why he described "bonds of earth" to be "surly". Is it assumed that you cannot enjoy what you might call "things under the sun"? And how can you touch the face of God? If the word "bonds" refers to "anything that stops you from being free to do what you want", what does "touching the face of God" mean? Did he try to consecrate the accident?