Does delaying a prayer until after midnight – for the purpose of attaining khushoo' (devotional humility) and performing Qiyam al-Layl (night vigil prayer) – make it a qada' (a prayer performed outside its prescribed time)? Is there a specific time for Qiyam al-Layl? What is the difference between Qiyam al-Layl and Tahajjud? And which of them yields greater reward?

Delaying the 'Isha prayer until after midnight without a valid excuse is reprehensible (makrooh), and may fall under the disagreement of those who say its time expires at midnight. The Prophet (peace be upon him) forbade sleeping before it. Scholars have differed regarding the end of the optional time for 'Isha, and the most preponderant opinion is that it extends until midnight. The majority of scholars hold that the time for 'Isha extends until Fajr, but delaying it without an excuse is reprehensible or forbidden (haram). Tahajjud is to pray after sleeping, and it is a form of night prayer (qiyam al-layl), and performing qiyam at the end of the night is superior.