This is an expression to be used when someone who has been through hell finally has something go right in their lives.

An unexpected blessing, a miracle, to show that God, who had apparently been slacking off for a while, has finally reappeared.
"After an agonizing journey with stage 4 cancer, she found out that the man she has secretly been in love with for 20 years has also been in love with her. Now she's cancer-free, and they're engaged. God is back from lunch."
by SneezyDwarf June 24, 2013
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