The Nature of Prayer - Section 1 Mishkat al-Masabih 800
Arabic hadith text
وَعَنْ جَابِرٍ قَالَ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «أَفْضَلُ الصَّلَاةِ طُولُ الْقُنُوتِ» . رَوَاهُ مُسلم
Translation
Jabir reported God’s Messenger as saying, “The most excellent prayer consists in long standing in prayer.” Muslim transmitted it.