Lyric discussion by methodlessman 

Cover art for Deliverance lyrics by Opeth

This song is about Satan.

the devil guides the day tells me what to say pours himself inside and snuffs the final light

deliverance thrown back at me

deliverance laughing at me

Perhaps the narrator is insane or actually under the control of Satan. I think the life code part means electrical impulses from his brain to his muscles(life code). Nothing, then he starts to think about killing and can't resist.

all over now forgotten why i needed this standing down disappear into the obscure resting days waiting for new disease biding time looked inside insanity

Waiting for new disease to me means that he is waiting for the urge to kill to come again.