Abu Hazim said, "I heard Sahl bin Saad say, 'I heard the Prophet ﷺ say, "I will go ahead of you to the Pond. Whoever comes to it will drink from it, and whoever drinks from it will never thirst again. Groups of people will come to me whom I will recognize and who will recognize me, then a barrier will be placed between me and them."'"Abu Hazim continued, "Numan bin Abu Ayyash heard me while I was narrating this to them, and he asked, 'Is this how you heard it from Sahl?'I replied, 'Yes.'He said, 'And I bear witness that I heard Abu Saeed Khudri add to it. He said, "I will say, 'They are from me,' but it will be said, 'You do not know what they introduced after you.' So I will say, 'Away with them, away with them, those who altered the religion after me.'"'"
سمعت سهل بن سعد يقول: سمعت النبي ﷺ يقول: أنا فرطكم على الحوض، من ورد شرب منه، ومن شرب منه لم يظمأ بعده أبدا، ليرد علي أقوام أعرفهم ويعرفوني، ثم يحال بيني وبينهم. قال أبو حازم: فسمعني النعمان بن أبي عياش، وأنا أحدثهم هذا، فقال: هكذا سمعت سهلا؟ فقلت: نعم، قال: وأنا أشهد على أبي سعيد الخدري لسمعته يزيد فيه، قال: إنهم مني، فيقال: إنك لا تدري ما بدلوا بعدك، فأقول: سحقا سحقا لمن بدل بعدي.
Bukhari narrated it in the Chapter on Tribulations (7050, 7051), and Muslim in the Chapter on Virtues (2290), both through the route of Yaqub bin Abdul-Rahman Qari, from Abu Hazim, and he mentioned it. See the rest of the hadiths on the Basin (Hawd) in the Book of Faith, in the collected chapters on faith in the Prophet ﷺ.