I came to the Prophet ﷺ while he was wearing a white garment and was asleep. Then I came to him again after he had woken up, and he said, "There is no servant who says, 'There is no god but Allah,' and then dies upon that, except that he will enter Paradise."
أتيت النبي ﷺ وعليه ثوب أبيض، وهو نائم، ثم أتيته وقد استيقظ، فقال: ما من عبد قال: لا إله إلا الله، ثم مات على ذلك إلا دخل الجنة.
Bukhari narrated it in the Book of Clothing (5827), and Muslim in the Book of Faith (94:154), both through Abdul-Warith (he is Ibn Saeed Anbari), from Husayn the teacher, from Ibn Burayda, that Yahya bin Yamar told him that Abu Aswad Daili told him that Abu Dharr told him, he said, and then he mentioned it.