The inquirer says, “I always delay the ‘isha prayer until midnight so that I may perform it in congregation with my wife. Afterwards, we offer as many rak’ahs of the night vigil prayers (qiyam al-layl) as Allah gives us the ability to perform. What is the ruling on delaying the ‘isha prayer until midnight?”

The authentic hadiths narrated from the Prophet (peace and blessings be upon him) indicate the preference of delaying the ‘isha prayer from when its time sets in until a third or half of the night has passed. Among these, is the hadith of Zayd Ibn Khalid al-Juhani (may Allah be pleased with him) who narrated that the Prophet (peace and blessings be upon him) said,
“If it were not that I would cause hardship for my Ummah, I would have commanded them to use the siwak before every prayer and to delay the ‘isha prayer until the last third of the night”
(recorded by al-Tirmidhi who declared the hadith to be good and authentic). In another hadith, Abu Huraira (may Allah be pleased with him) narrated that the Prophet (peace and blessings be upon him) said,
“If it were not that I would cause hardship for my Ummah, I would have commanded them to delay the ‘isha prayer to the third or half of the night” (recorded by al-Tirmidhi who declared the hadith to be good and authentic).
 

Imam al-Nawawi noted in Al-Majmu ‘(3:59–60) after mentioning a number of hadiths on the virtue of delaying the ‘isha prayer,
“These are authentic hadiths establishing the virtue of delaying the ‘isha prayer. This is the position of Abu Hanifa, Ahmad, Ishaq, and others. Al-Tirmidhi related it as the view of the majority of the scholars among the Companions and Successors. Ibn al-Mundhir also transmitted it from Ibn Mas‘ud, Ibn ‘Abbas, al-Shafi‘i, and Abu Hanifa … and it is the stronger in proof due to the aforementioned hadiths.”

The above ruling applies to those who know that delaying the prayer will not cause them to be overcome by sleep or laziness. Otherwise, it is obligatory to hasten to perform the prayer at the beginning of its time. The hadith scholar Ibn Hajar said in Fath Al-Bari (2:48),
“Whoever has the strength to delay it, i.e., the ‘isha prayer, is not overtaken by sleep, and such delay does not impose hardship upon the congregation, then for him, delaying it is preferable. Al-Nawawi affirmed this in his commentary on Muslim, and it is the chosen view adopted by many hadith scholars from among the Shafi‘is and others.”

It is important to note that the night begins at sunset and ends at the break of dawn. The interval between these two points constitutes the night. To determine the middle of the night, the total hours between sunset and dawn are calculated then divided in half. The resulting number is then added to the time of sunset, thereby establishing the time of the middle of the night. Similarly, to determine the third of the night, the total hours between dawn and sunset are divided by three and the resulting number is added to the time of sunset.

And Allah the Almighty knows best.