Sahih al-Bukhari 3257
صحيح البخاري#3257SahihNarrated Sahl bin Sa`d:The Prophet (ﷺ) said, "Paradise has eight gates, and one of them is called Ar-Raiyan through which none will enter but those who observe fasting
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: 59:67