We were standing at a place far from the main standing area when Ibn Murba came to us and said, "I am the messenger of the Messenger of Allah ﷺ to you. He says, 'Remain at your ritual stations, for today you are upon a legacy from the legacy of Ibrahim.'"
حدثنا أبو بكر بن أبي شيبة حدثنا سفيان بن عيينة عن عمرو بن دينار عن عمرو بن عبد الله بن صفوان
كنا وقوفا في مكان تباعده من الموقف فأتانا ابن مربع فقال إني رسول رسول الله ﷺ إليكم يقول كونوا على مشاعركم فإنكم اليوم على إرث من إرث إبراهيم
Its isnad is sahih. Abu Dawud narrated it in the book of Hajj, chapter on the place of standing at Arafah, no. 1919, from the hadith of Sufyan by this route. Tirmidhi said in no. 883 that it is hasan sahih, and Ibn Khuzayma graded it sahih in no. 2818, as did Hakim in 1/462 and Dhahabi.