Aged aristo sacked, thank God (3,7)

I believe the answer is:

deo gratias

'thank god' is the definition.
('deo gratias' is means thank God in Latin)

'aged aristo sacked' is the wordplay.
'sacked' indicates an anagram.
'aged'+'aristo'='agedaristo'
'agedaristo' with letters rearranged gives 'DEO GRATIAS'.

(Another definition for deo gratias that I've seen is " thank God".)

I've seen this clue in The Guardian.

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