ENOfficial
Narrated Abu-Wail: `Abdullah said, "One night I offered the Tahajjud prayer with the Prophet (ﷺ) and he kept on standing till an ill-thought came to me." We said, "What was the ill-thought?" He said, "It was to sit down and leave the Prophet (standing)."
Source: sunnah.com
Other translations
Arabic
حَدَّثَنَا سُلَيْمَانُ بْنُ حَرْبٍ، قَالَ حَدَّثَنَا شُعْبَةُ، عَنِ الأَعْمَشِ، عَنْ أَبِي وَائِلٍ، عَنْ عَبْدِ اللَّهِ ـ رضى الله عنه ـ قَالَ صَلَّيْتُ مَعَ النَّبِيِّ صلى الله عليه وسلم لَيْلَةً، فَلَمْ يَزَلْ قَائِمًا حَتَّى هَمَمْتُ بِأَمْرِ سَوْءٍ. قُلْنَا وَمَا هَمَمْتَ قَالَ هَمَمْتَ أَنْ أَقْعُدَ وَأَذَرَ النَّبِيَّ صلى الله عليه وسلم.
sunnah.com