I witnessed Marwan ask Abu Hurairah, "How did you hear the Messenger of Allah ﷺ pray over the deceased?"Abu Hurairah replied, "Along with what you just said?"Marwan said, "Yes." This referred to a conversation that had taken place between them earlier.Abu Hurairah said, "He would say, 'O Allah, You are its Lord, You created it, You guided it to Islam, You took its soul, and You know best its hidden state and its open state. We have come to You as intercessors, so forgive him.'"
حدثنا أبو معمر عبد الله بن عمرو حدثنا عبد الوارث حدثنا أبو الجلاس عقبة بن سيار
شهدت مروان سأل أبا هريرة كيف سمعت رسول الله ﷺ يصلي على الجنازة قال أمع الذي قلت قال نعم قال كلام كان بينهما قبل ذلك قال أبو هريرة اللهم أنت ربها وأنت خلقتها وأنت هديتها للإسلام وأنت قبضت روحها وأنت أعلم بسرها وعلانيتها جئناك شفعاء فاغفر له
Its isnad is hasan. Ahmad reported it: 2/363, and Nasai in Amal al-Yawm wal-Layla, no. 1078, from the hadith of Abdul-Warith, through him from Ali bin Shammakh. Ibn Hibban mentioned him among the trustworthy narrators, and Saeed bin Aas sent him to Madinah. Hafiz graded it hasan in Futuhat Rabbaniya, 5/176.