(19) باب الأَكْسِيَةِ وَالْخَمَائِصِ
Narrated `Aisha and `Abdullah bin `Abbas:
When the disease of Allah's Messenger (ﷺ) got aggravated, he covered his face with a Khamisa, but when he became short of breath, he would remove it from his face and say, "It is like that! May Allah curse the Jews Christians because they took the graves of their prophets as places of worship." By that he warned his follower of imitating them, by doing that which they did.
Reference: Sahih al-Bukhari 5815, 5816
In-book reference: Book 77, Hadith 33
USC-MSA web (English) reference(deprecated numbering scheme): Vol. 7, Book 72, Hadith 706