Should one who has outstanding missed prayers not pray nafl?

Question

The merits that have been described for nafl prayers [apply] after complete observance of the fard and wajib obligations. Accordingly, the elders have said that as long as the prayers missed over a lifetime have not been made up, one should make them up in place of nafl prayers — [in place of] duha and the like, or the five daily.

Answer

One who still has fard prayers owed as qada' should take care to perform the qada' prayers. In such a situation, devoting oneself to nafl prayers while not performing the qada' is not commendable, and is also unwise, although it will not be ruled that the nafl prayers have become fasid (invalid).

Source: Fatawa Mahmudiyya

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