Jami` at-Tirmidhi 412
جامع الترمذي#412Sahihحَدَّثَنَا قُتَيْبَةُ، وَبِشْرُ بْنُ مُعَاذٍ الْعَقَدِيُّ، قَالاَ حَدَّثَنَا أَبُو عَوَانَةَ، عَنْ زِيَادِ بْنِ عِلاَقَةَ، عَنِ الْمُغِيرَةِ بْنِ شُعْبَةَ، قَالَ صَلَّى رَسُولُ اللَّهِ صلى الله عليه وسلم حَتَّى انْتَفَخَتْ قَدَمَاهُ فَقِيلَ لَهُ أَتَتَكَلَّفُ هَذَا وَقَدْ غُفِرَ لَكَ مَا تَقَدَّمَ مِنْ ذَنْبِكَ وَمَا تَأَخَّرَ قَالَ " أَفَلاَ أَكُونُ عَبْدًا شَكُورًا " . قَالَ وَفِي الْبَابِ عَنْ أَبِي هُرَيْرَةَ وَعَائِشَةَ . قَالَ أَبُو عِيسَى حَدِيثُ الْمُغِيرَةِ بْنِ شُعْبَةَ حَدِيثٌ حَسَنٌ صَحِيحٌ .
Al-Mughirah bin Shu'bah narrated:"Allah's Messenger (S) performed Salat until his feet were swollen, so it was said to him: 'You burden yourself like this, while your past and future sins have been forgiven?' He said: 'Shouldn't I be a grateful worshipper?
Scholarly Authentication
The label above is the grade most of these scholars gave — one dissenting opinion no longer speaks for all of them. If any scholar calls a narration fabricated, that verdict is shown instead, whatever the others say. Each scholar's own wording:
In-book reference: 2:265