What is the benefit of praying istikhaarah when things are already decreed?

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Is it permissible to pray “O Allah, if this matter is bad for me, then make it good and decree it for me”?
Not taking appropriate means on the grounds of putting one’s trust in Allaah

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Related Answers:
The du’aa’ “O Allaah, we do not ask You to overturn the decree but we ask You to help us bear its impact”
Ruling on offering du‘aa’ in congregation
She made du’aa’ and her prayer wasn’t answered, and she said, There is no God
Is it permissible to pray “O Allah, if this matter is bad for me, then make it good and decree it for me”?
Not taking appropriate means on the grounds of putting one’s trust in Allaah

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