I saw Ibn Umar touch the Black Stone, then kiss his hand and say, "I have not stopped doing this since I saw the Messenger of Allah ﷺ do it."
حدثنا عبد الله بن محمد وسمعته أنا من عبد الله بن محمد حدثنا أبو خالد الأحمر عن عبيد الله
رأيت ابن عمر استلم الحجر ثم قبل يده وقال ما تركته منذ رأيت رسول الله ﷺ يفعله
Its isnad is sahih. Abu Khalid Ahmar is Sulayman bin Hayan, whose reliability was established earlier at 855, and we add here that Bukhari discussed him in al-Kabir 2/2/9. He is among the teachers of Ahmad, but here Ahmad narrated from him through his colleague Abu Bakr Ibn Abu Shayba. The hadith was also narrated by the two Shaykhs, as in al-Muntaqa 2538, and see 5239.