Don't be so optimistic — it's past praying for (8)
I believe the answer is:
hopeless
'don't be so optimistic' is the definition.
I can't tell whether this definition defines the answer.
'it's past praying for' is the wordplay.
I cannot quite understand how this works, but
'it's' could be 'es' ('e' can mean 'electronic' which is similar to 'IT') and 'es' is found within the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for hopeless that I've seen before include "Despairing - pathetic" , "Inefficient" , "Having no reason expect a good outcome" , "Incompetent" , "Unachievable" .)