The time of Tahajjud: nafl prayed before sleeping

Question

A person prays nafl and witr at ten or eleven o’clock and goes to sleep [on the understanding] that if he does not wake up for Tahajjud, the night nafl will be credited to him as Tahajjud. This person wakes at twelve or one o’clock, but does not pray Tahajjud at that time, with the thought that he might then not be able to wake later for the morning prayer.

Answer

The true time of Tahajjud is the last part of the night, after having slept and risen. If one cannot rise at that time, one will obtain the reward by praying [it] before sleeping as well. And the later one prays it before going to sleep, the better: for example, if he is going to sleep at one o’clock, let him pray it at that time.

Source: Fatawa Mahmudiyya

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