﴿ ۞ إِنَّ رَبَّكَ يَعْلَمُ أَنَّكَ تَقُومُ أَدْنَىٰ مِن ثُلُثَىِ ٱلَّيْلِ وَنِصْفَهُۥ وَثُلُثَهُۥ وَطَآئِفَةٌۭ مِّنَ ٱلَّذِينَ مَعَكَ ۚ وَٱللَّهُ يُقَدِّرُ ٱلَّيْلَ وَٱلنَّهَارَ ۚ عَلِمَ أَن لَّن تُحْصُوهُ فَتَابَ عَلَيْكُمْ ۖ فَٱقْرَءُوا۟ مَا تَيَسَّرَ مِنَ ٱلْقُرْءَانِ ۚ عَلِمَ أَن سَيَكُونُ مِنكُم مَّرْضَىٰ ۙ وَءَاخَرُونَ يَضْرِبُونَ فِى ٱلْأَرْضِ يَبْتَغُونَ مِن فَضْلِ ٱللَّهِ ۙ وَءَاخَرُونَ يُقَٰتِلُونَ فِى سَبِيلِ ٱللَّهِ ۖ فَٱقْرَءُوا۟ مَا تَيَسَّرَ مِنْهُ ۚ وَأَقِيمُوا۟ ٱلصَّلَوٰةَ وَءَاتُوا۟ ٱلزَّكَوٰةَ وَأَقْرِضُوا۟ ٱللَّهَ قَرْضًا حَسَنًۭا ۚ وَمَا تُقَدِّمُوا۟ لِأَنفُسِكُم مِّنْ خَيْرٍۢ تَجِدُوهُ عِندَ ٱللَّهِ هُوَ خَيْرًۭا وَأَعْظَمَ أَجْرًۭا ۚ وَٱسْتَغْفِرُوا۟ ٱللَّهَ ۖ إِنَّ ٱللَّهَ غَفُورٌۭ رَّحِيمٌۢ ﴾

“BEHOLD, [O Prophet,] thy Sustainer knows that thou keepest awake [in prayer] nearly two-thirds of the night, or one-half of it, or a third of it, together with some of those who follow thee. And God who determines the measure of night and day, is aware that you would never grudge it: and therefore He turns towards you in His grace. Recite, then, as much of the Qur’an as you may do with ease. He knows that in time there will be among you sick people, and others who will go about the land in search of God's bounty, and others who will fight in God’s cause. Recite, then, [only] as much of it as you may do with ease, and be constant in prayer, and spend in charity, and [thus] lend unto God a goodly loan: for whatever good deed you may offer up in your own behalf, you shall truly find it with God - yea, better, and richer in reward. And [always] seek God's forgiveness: behold, God is much-forgiving, a dispenser of grace!”

Assuredly your Lord knows that you stand vigil less than two thirds of the night or at times a half of it or a third of it if read wa-nisfihi wa-thuluthihi then these constitute a supplement to thuluthay ‘two thirds’; if read wa-nisfahu wa-thuluthahu then a supplement to adnā ‘less than’ — his keeping vigil in the way mentioned is in accordance with what was enjoined on him at the beginning of this sūra — along with a group of those with you wa-tā’ifatun mina’lladhīna ma‘aka constitutes a supplement to the subject of the verb taqūmu ‘you stand vigil’ but it may also constitute although it is not certain a separating clause. The keeping vigil by some of his companions in this way indicates their emulation of him. Some of them could not tell how much of the night they had spent in prayer and how much of it had remained and would therefore keep vigil all night as a precaution; and so they used to keep vigil in this way for a whole year or more with their feet swollen until God alleviated matters for them. He exalted be He says and God keeps measures He keeps count of the night and the day. He knows that an softened in place of the hardened form its subject having been omitted that is to say annahu you will not be able to keep count of it that is the length of the night so that you may perform the vigil at the time in which it is required unless you stay up all night which is hard on you and so He has relented to you making you revert to what is easier. So recite as much as is feasible of the Qur’ān during prayer by performing as much prayer as is feasible. He knows that an softened in place of the hardened form that is to say annahu some of you will be sick while others will be travelling in the land seeking the bounty of God seeking of His provision through commerce and otherwise and others will be fighting in the way of God for each of the three groups mentioned the keeping of nightly vigil is hard and so God has alleviated things for them by enjoining on them what is feasible.