The Statement of Allah the Exalted: "That Allah may forgive you your sins of the past and the future and complete His Favour on you and guide you on the Straight Path." (V.48:2)
Narrated Al-Mughira: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)?"
Reference
Sahih al-Bukhari 4836
In-book reference
Book 65, Hadith 357
USC-MSA web (English)
Vol. 6, Book 60, Hadith 360
Translation by Dr. M. Muhsin Khan · Language: EN
Sahih
Arabic Text
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 ".