Counting maintenance given without obligation towards the mahr

Question

Question: Zayd gave his wife, say, 50 rupees with the intention of maintenance (nafaqa); then it became known that this was not obligatory (wajib) upon him. Can Zayd count it towards the mahr, or is a fresh taking of possession (qabd) necessary, or does he have no right to take it?

Answer

This particular ruling (juz’iyya) has not come before my eyes explicitly, but I will quote another particular ruling which can serve as its analogue; through it the ruling of the case in question will also become known.

Source: Fatawa Mahmudiyya

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