The Messenger of Allah ﷺ said, "Death will be brought forward in the form of a ram, white flecked with black, and a caller will cry out, 'People of Paradise!' They will stretch their necks and look, and he will ask, 'Do you recognize this?' They will answer, 'Yes, this is death.' Every one of them will have seen it. Then he will call out, 'People of the Fire!' They will stretch their necks and look, and he will ask, 'Do you recognize this?' They will answer, 'Yes, this is death.' Every one of them will have seen it. Then it will be slaughtered, and he will say, 'People of Paradise, this is eternity, there is no more death. People of the Fire, this is eternity, there is no more death.'"Then he recited, "And warn them of the Day of Regret, when the matter will be decided, while they are heedless" [Maryam 19:39]. These are heedless in the manner of the people of this world, "and they do not believe" [Maryam 19:39].
قال رسول الله ﷺ: يؤتى بالموت كهيئة كبش أملح، فينادي مناد: يا أهل الجنة، فيشرئبون وينظرون، فيقول: هل تعرفون هذا؟ فيقولون: نعم، هذا الموت، وكلهم قد رآه، ثم ينادي: يا أهل النار، فيشرئبون وينظرون، فيقول: وهل تعرفون هذا؟ فيقولون: نعم، هذا الموت، وكلهم قد رآه، فيذبح ثم يقول: يا أهل الجنة خلود فلا موت، ويا أهل النار خلود فلا موت، ثم قرأ: {وأنذرهم يوم الحسرة إذ قضي الأمر وهم في غفلة} [مريم: ٣٩]، وهؤلاء في غفلة أهل الدنيا {وهم لا يؤمنون} [مريم: ٣٩].
Bukhari related it in the tafsir (4730), and Muslim in Paradise (2849), both of them through Amash, who said, Abu Salih narrated to us, from Abu Saeed Khudri, who said, and he mentioned it. The wording given is that of Bukhari, and Muslim's wording is similar.