Compiled by Imam Muhammad al-Bukhari
حَدَّثَنَا صَدَقَةُ بْنُ الْفَضْلِ، أَخْبَرَنَا ابْنُ عُيَيْنَةَ، حَدَّثَنَا زِيَادٌ، أَنَّهُ سَمِعَ الْمُغِيرَةَ، يَقُولُ قَامَ النَّبِيُّ صلى الله عليه وسلم حَتَّى تَوَرَّمَتْ قَدَمَاهُ فَقِيلَ لَهُ غَفَرَ اللَّهُ لَكَ مَا تَقَدَّمَ مِنْ ذَنْبِكَ وَمَا تَأَخَّرَ قَالَ " أَفَلاَ أَكُونُ عَبْدًا شَكُورًا ".
The Prophet (ﷺ) used to offer night prayers till his feet became swollen. Somebody said, to him," "Allah has forgiven you, your faults of the past and those to follow." On that, he said, "Shouldn't I be a thankful slave of Allah)?"