Answered by Shaykh Hamza Karamali, SunniPath Academy Teacher
If I make up an audible Salaat in the time of a silent Salaat, should I pray it silent or audible, and vice versa?
In the Name of Allah, Most Merciful and Compassionate
Shaykh al-Islam Zakariyya al-Ansari said, “Whether one prays loudly or silently when making up a prescribed prayer is determined by the time during which one is performing the make-up prayer, not the time of the original prayer.” (Fath al-Wahhab in the margins of Hashiyat al-Jamal, 1.360)
In other words, if one is making up the maghrib prayer during the time of the zuhr prayer, it is recommended to recite silently to oneself because one is performing the makeup in the time of a silent prayer. But if one is making up the zuhr prayer during the time of the maghrib prayer, it is recommended to recite aloud because one is performing the makeup in the time of an audible prayer.
Note that one’s prayer is valid regardless of whether one recites out loud or to oneself. The choice between the two is a choice of optimality, not a choice of validity.
And Allah knows best.
Hamza.