Praise be to Allah.
Tahajjud, Witr and Taraweeh all come under the heading of qiyaam al-layl (night prayers) or Taraweeh, but Taraweeh refers specifically to qiyaam al-layl in Ramadan.
The words of ‘Aa’ishah (may Allah be pleased with her) in fact refer to the night prayers of the Messenger (blessings and peace of Allah be upon him), which refers to every prayer that he offered at night.
Al-Bukhaari (3569) and Muslim (738) narrated from Abu Salamah ibn ‘Abd ar-Rahmaan, that he asked ‘Aa’ishah (may Allah be pleased with her): How did the Messenger of Allah (blessings and peace of Allah be upon him) pray during Ramadan? She said: He did not pray more, in Ramadan or at any other time, than eleven rak‘ahs. He would pray four, and do not ask how beautiful and long they were. Then he would pray four, and do not ask how beautiful and long they were. Then he would pray three. I said: O Messenger of Allah, do you sleep before you pray Witr? He said: “My eyes sleep but my heart does not sleep.”
An-Nawawi (may Allah have mercy on him) said:
It was narrated from her (may Allah be pleased with her) in al-Bukhaari that he (blessings and peace of Allah be upon him) prayed at night seven or nine rak‘ahs. After that, al-Bukhaari and Muslim narrated from the hadith of Ibn ‘Abbaas that he (blessings and peace of Allah be upon him) prayed at night thirteen rak‘ahs, and two rak‘ahs after dawn broke, the Sunnah of Fajr. According to the hadith of Zayd ibn Khaalid, he (blessings and peace of Allah be upon him) prayed two brief rak‘ahs then two lengthy ones – and he quoted the hadith, and at the end of it he said: that was thirteen. Al-Qaadi said: The scholars said: In these hadiths, each of them – Ibn ‘Abbaas, Zayd and ‘Aa’ishah – narrated what he or she saw. End quote.
Each of these Sahaabis mentioned the total of what the Prophet (blessings and peace of Allah be upon him) used to pray at night, which includes tahajjud and other prayers.
Al-Haafiz ibn Hajar (may Allah have mercy on him) stated that the words of ‘Aa’ishah, that the Prophet (blessings and peace of Allah be upon him) prayed at night seven or nine rak‘ahs, mean that that happened at different times.
And what was meant by her words when she said that he did not pray more, in Ramadaan or at any other time, than eleven rak‘ahs is that this was the most that he used to pray at night, and he did not do more than that.
With regard to her saying that the Prophet (blessings and peace of Allah be upon him) prayed thirteen rak‘ahs, al-Haafiz ibn Hajar said that there are two possible meanings for this: it may be that she added the Sunnah of ‘Isha’ to the night prayers, because they are also offered at night, or it may be that she added the two brief rak‘ahs with which the Prophet (blessings and peace of Allah be upon him) used to begin the night prayers. Al-Haafiz said: The latter is more likely to be correct in my view. Fath al-Baari
Thus it is clear that what ‘Aa’ishah (may Allah be pleased with her) was referring to was the total of what the Prophet (blessings and peace of Allah be upon him) used to pray at night. This is what the scholars understood from her hadith.
Please see also the answer to question no. 9036
And Allah knows best.
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