"‏ مَنْ قَالَ حِينَ يُصْبِحُ اللَّهُمَّ إِنِّي أَصْبَحْتُ أُشْهِدُكَ وَأُشْهِدُ حَمَلَةَ عَرْشِكَ وَمَلاَئِكَتَكَ وَجَمِيعَ خَلْقِكَ أَنَّكَ أَنْتَ اللَّهُ لاَ إِلَهَ إِلاَّ أَنْتَ وَحْدَكَ لاَ شَرِيكَ لَكَ وَأَنَّ مُحَمَّدًا عَبْدُكَ وَرَسُولُكَ إِلاَّ غُفِرَ لَهُ مَا أَصَابَ فِي يَوْمِهِ ذَلِكَ مِنْ ذَنْبٍ وَإِنْ قَالَهَا حِينَ يُمْسِي غُفِرَ لَهُ مَا أَصَابَ تِلْكَ اللَّيْلَةَ ‏"

The Prophet (ﷺ) said: If anyone says in the morning: "O Allah! in the morning we call Thee, the bearers of Thy Throne, Thy angels, and all Thy creatures to witness that Thou art Allah than Whom there is no god, Thou being alone and without a partner, and that Muhammad is Thy servant and Thy Apostle," Allah will forgive him any sins that he commits that day; and if he repeats them in the evening. Allah will forgive him any sins he commits that night.