Tafsir of Surah Az-Zumar 39:9
﴿أَمَّنْ هُوَ قَانِتٌ آنَاءَ اللَّيْلِ سَاجِدًا وَقَائِمًا يَحْذَرُ الْآخِرَةَ وَيَرْجُو رَحْمَةَ رَبِّهِ قُلْ هَلْ يَسْتَوِي الَّذِينَ يَعْلَمُونَ وَالَّذِينَ لَا يَعْلَمُونَ إِنَّمَا يَتَذَكَّرُ أُولُو الْأَلْبَابِ﴾
Translation of the meaning
Is one who is devoutly obedient during periods of the night, prostrating and standing [in prayer], fearing the Hereafter and hoping for the mercy of his Lord, [like one who does not]? Say, "Are those who know equal to those who do not know?" Only they will remember [who are] people of understanding.
English Translation - Noor International Center — v1.1.2 · QuranEnc.comThe words of the two imams are given in their original Arabic, verbatim, with references.
Shaykh al-Islam Ibn Taymiyyah
وكل من خشيه، وأطاعه، وترك معصيته، فهو عالم«الحسنة والسيئة» 1/63فإن القنوت هو إدامة العبادة، سواء كان في حال القيام، أو الركوع أو السجود«الفتاوى الكبرى لابن تيمية» 2/120