Tafsir of Surah Al-Muzzammil 73:20
﴿إِنَّ رَبَّكَ يَعْلَمُ أَنَّكَ تَقُومُ أَدْنَىٰ مِن ثُلُثَيِ اللَّيْلِ وَنِصْفَهُ وَثُلُثَهُ وَطَائِفَةٌ مِّنَ الَّذِينَ مَعَكَ وَاللَّهُ يُقَدِّرُ اللَّيْلَ وَالنَّهَارَ عَلِمَ أَن لَّن تُحْصُوهُ فَتَابَ عَلَيْكُمْ فَاقْرَءُوا مَا تَيَسَّرَ مِنَ الْقُرْآنِ عَلِمَ أَن سَيَكُونُ مِنكُم مَّرْضَىٰ وَآخَرُونَ يَضْرِبُونَ فِي الْأَرْضِ يَبْتَغُونَ مِن فَضْلِ اللَّهِ وَآخَرُونَ يُقَاتِلُونَ فِي سَبِيلِ اللَّهِ فَاقْرَءُوا مَا تَيَسَّرَ مِنْهُ وَأَقِيمُوا الصَّلَاةَ وَآتُوا الزَّكَاةَ وَأَقْرِضُوا اللَّهَ قَرْضًا حَسَنًا وَمَا تُقَدِّمُوا لِأَنفُسِكُم مِّنْ خَيْرٍ تَجِدُوهُ عِندَ اللَّهِ هُوَ خَيْرًا وَأَعْظَمَ أَجْرًا وَاسْتَغْفِرُوا اللَّهَ إِنَّ اللَّهَ غَفُورٌ رَّحِيمٌ﴾
Translation of the meaning
Indeed, your Lord knows, [O Muḥammad], that you stand [in prayer] almost two thirds of the night or half of it or a third of it, and [so do] a group of those with you. And Allāh determines [the extent of] the night and the day. He has known that you [Muslims] will not be able to do it and has turned to you in forgiveness, so recite what is easy [for you] of the Qur’ān. He has known that there will be among you those who are ill and others traveling throughout the land seeking [something] of the bounty of Allāh and others fighting for the cause of Allāh. So recite what is easy from it and establish prayer and give zakāh and loan Allāh a goodly loan. And whatever good you put forward for yourselves - you will find it with Allāh. It is better and greater in reward. And seek forgiveness of Allāh. Indeed, Allāh is Forgiving and Merciful.
English Translation - Noor International Center — v1.1.2 · QuranEnc.comThe words of the two imams are given in their original Arabic, verbatim, with references.
Imam Ibn al-Qayyim
رد النصوص المحكمة الصريحة الصحيحة في تعيين قراءة فاتحة الكتاب فرضا بالمتشابه من قوله: {فاقرءوا ما تيسر منه} [المزمل: 20] وليس ذلك في الصلاة، وإنما هو بدل عن قيام الليل،«إعلام الموقعين عن رب العالمين» 2/218والضرب فى الأرض هو السفر،«طريق الهجرتين وباب السعادتين» 1/377