Zikr for Forgiveness of Sins
Anas bin Malik narrated that the Prophet (ﷺ) said that if anyone says the following dua in the morning, then Allah will forgive him for sins which he committed on that day, and if he says it in the evening, then Allah will forgive him for the sins which he committed on that night.
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.
Allahumma innî asbahtu ush-hiduka, wa ush-hidu hamalata arshika, wa malaa ‘ikatika, wa jamii a’ khalqika, annaka antal-laahu, laa ilaaha illaa anta, wahdaka laa sharîka laka, wa anna Muhammadan abduka wa rasuluk.
“O Allah, verily I have reached the morning and call on You, the bearers of Your throne, Your angels, and all of Your creation to witness that You are Allah, none has the right to be worshipped except You, Alone, without partner and that Muhammad is Your Servant and Messenger. (Sunan Abu Dawood)
(سنن أبو داود, كتاب الأدب)