The Messenger of Allah ﷺ recited "If I ask you about anything after this, then do not keep me as a companion. You have already received from me an excuse" [Kahf 18:76].
حدثنا محمد بن عبد الله بن نمير حدثنا أبو داود عمر بن سعد عن يحيى بن زكريا بن أبي زائدة عن حمزة عن أبي إسحاق عن سعيد بن جبير
أن رسول الله ﷺ قرأ {إن سألتك عن شيء بعدها فلا تصاحبني قد بلغت من لدني عذرا}
Its chain of transmission is sahih. "Abu Dawud" here refers to Umar bin Saad al-Hafari, who is trustworthy, and his name occurs frequently in the chains.The hadith was narrated by Abu Dawud, 4/32, no. 3984, in the chapter on virtues, in the section on the virtues of Khidr ﷺ, and similarly in Muslim, 4/1850, no. 2380, and Ibn Abu Shayba, 7/32 (Dar al-Fikr edition), and Hakim, 2/574, where Dhahabi remained silent about it. It is among the additional reports.