The Messenger of Allah Muhammad (ﷺ) entered the masjid and there was a man who had finished his prayer and he was reciting the tashahhud. He said: "Allahumma inni as'aluka ya Allah! Bi-annakal-Wahidul-Ahad us-Samad, alladhi lam yalid wa lam yowled, wa lam yakun lahu kufuwan ahad, an taghfirali dhunubi, innaka antal-Ghafurur-Rahim (O Allah, I ask of You, O Allah, as You are the One, the Only, the Self-Sufficient Master, Who begets not nor was He begotten, and there is None equal or comparable to Him, forgive me my sins, for You are the Oft-Forgiving, Most Merciful.)" The Messenger of Allah (ﷺ) said: "He has been forgiven," three times.
اللّٰهُمَّ إِنِّي أَسْأَلُكَ يَا اللَّهُ بِأَنَّكَ الْوَاحِدُ الأَحَدُ الصَّمَدُ الَّذِي لَمْ يَلِدْ وَلَمْ يُولَدْ وَلَمْ يَكُنْ لَهُ كُفُوًا أَحَدٌ
Allaahumma 'innee 'as'aluka yaaAllaahu bi'annakal-Waahidul-'Ahadus-Samadul-lathee, lam yalid wa lam yoolad, wa lam yakun lahu kufuwan 'Ahad, 'an taghfira lee thunoobee 'innaka 'Antal-Ghafoorur-Raheem.
O Allah , I ask You . O Allah , You are the One , the Only, Self-Sufficient Master, Who was not begotten and begets not and none is equal to Him . Forgive me my sins , surely you are Forgiving, Merciful.
Reference: An-Nasa'i 3/52, Ahmad 4/338. See also Al-Albani, Sahih An-Nasa'i 1/280 and Sifat Salatun-Nabi, pg. 204.
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