Credit deity with emergency (6)
I believe the answer is:
crisis
'emergency' is the definition.
(a crisis is an emergency)
'credit deity' is the wordplay.
'credit' becomes 'cr' (abbreviation).
'deity' becomes 'isis' (Isis is an example).
'cr'+'isis'='CRISIS'
'with' is the link.
(Other definitions for crisis that I've seen before include "a difficult situation" , "Crucial stage in a series of events" , "Serious or crucial situation" , "Decisive moment, turning point" , "Time of decision or acute danger" .)