Sahih al-Bukhari 1344
صحيح البخاري#1344SahihNarrated `Uqba bin 'Amir:One day the Prophet (ﷺ) went out and offered the funeral prayers of the martyrs of Uhud and then went up the pulpit and said, "I will pave the way for you as your predecessor and will be a witness on you. By Allah! I see my Fount (Kauthar) just now and I have been given the keys of all the treasures of the earth (or the keys of the earth). By Allah! I am not afraid that you will worship others along with Allah after my death, but I am afraid that you will fight with one another for the worldly things
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Every narration in Sahih al-Bukhari is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 23:99