Then Allah says,
[إِنَّ رَبَّكَ 
يَعْلَمُ أَنَّكَ تَقُومُ أَدْنَى مِن ثُلُثَىِ الَّيْلِ وَنِصْفَهُ وَثُلُثَهُ 
وَطَآئِفَةٌ مِّنَ الَّذِينَ مَعَكَ]
(Verily, your Lord knows that you do stand a little less than two-thirds of 
the night, or half the night, or a third of the night, and also a party of those 
with you.) meaning, sometimes like this and sometimes like that, and all of 
these are done unintentionally. However, you all are not able to be consistent 
with the night prayer Allah has commanded you, because it is difficult for you. 
Thus, Allah says,
[وَاللَّهُ يُقَدِّرُ 
الَّيْلَ وَالنَّهَارَ]
(And Allah measures the night and the day.) meaning, sometimes the night and 
day are equal, and sometimes one of them will be longer or shorter than the 
other.
[عَلِمَ أَلَّن 
تُحْصُوهُ فَتَابَ]
(He knows that you are unable to pray the whole night,) meaning, the 
obligation which He prescribed for you.
[مَا تَيَسَّرَ مِنَ 
الْقُرْءَانِ عَلِمَ]
(So, recite you of the Qur'an as much as may be easy.) meaning, without 
specification of any set time. This means, stand and pray during the night as 
much as is easy (for you). Allah uses the term recitation (Qira'ah) to mean 
prayer (Salah). This is as Allah says in Surah Subhan (Al-Isra'),
[وَلاَ تَجْهَرْ 
بِصَلاتِكَ]
(And offer your Salah neither aloud) (17:110) meaning, your recitation.
[وَلاَ تُخَافِتْ 
بِهَا]
(Nor in low voice.) (17:110) Then Allah says,
[أَن سَيَكُونُ 
مِنكُمْ مَّرْضَى وَءَاخَرُونَ يَضْرِبُونَ فِى الاٌّرْضِ يَبْتَغُونَ مِن فَضْلِ 
اللَّهِ وَءَاخَرُونَ يُقَـتِلُونَ فِى سَبِيلِ اللَّهِ فَاقْرَءُواْ]
(He knows that there will be some among you sick, others traveling through 
the land, seeking of Allah's bounty, yet others fighting in Allah's cause.) 
meaning, He knows that there will be people of this nation who will have excuses 
for not praying the (voluntary) night prayer. They are those who are ill and 
therefore they are not able to perform it, and those who are traveling in the 
land seeking the bounty of Allah in business and trade, and others who will be 
busy with that which is more important to them. An example of this is going on 
expeditions to fight in the way of Allah. This Ayah, rather, this entire Surah 
was revealed in Makkah even though fighting was not legislated until after it 
was revealed. Thus, it is among the greatest of the signs of prophethood, 
because it informs about unseen matters of the future. Thus, Allah says,
[مَا تَيَسَّرَ 
مِنْهُ وَأَقِيمُواْ]
(So recite as much of the Qur'an as may be easy,) meaning, stand and pray at 
night whatever is easy for you to do of it. Allah said;
[وَأَقِيمُواْ 
الصَّلوةَ وَآتُواْ الزَّكَوةَ]
(and perform Salah and give Zakah,) meaning, establish your obligatory 
prayers and pay your obligatory Zakah. This is a proof for those who say that 
Zakah was made obligatory in Makkah, but the various amounts of Nisab and how 
much was to be given was clarified in Al-Madinah. And Allah knows best. Ibn 
`Abbas, `Ikrimah, Mujahid, Al-Hasan, Qatadah and others from the Salaf have 
said, "Verily, this Ayah abrogated the standing for prayer at night that Allah 
previously made obligatory for the Muslims.'' It has been confirmed in the Two 
Sahihs that the Messenger of Allah said to a man,
«خَمْسُ صَلَوَاتٍ 
فِي الْيَوْمِ وَاللَّيْلَة»
(Five obligatory prayers during a day and a night (are obligatory).)'' The 
man said, "Is there anything other than this (of prayer) that is obligatory upon 
me'' The Messenger of Allah replied,
«لَا، إِلَّا أَنْ 
تَطَوَّع»
(No, except what you may do voluntarily.)