"
you can sharpen your knife
"Offer me that deathless death"
He is asking her to spare him in death even when he has sinned. "Have mercy on me and my sinning" as said in the line previous. Offer me the death that is no deathless meaning, he wants death without dying. Basically a spirit made to wander but still alive. This song is thought too deeply upon but some explaination I suppose is required to help us comprehend the lyrics of songs.
"Offer me that deathless death"