Iyas reported on the authority of his father: We went along with Allah's Messenger (ﷺ) to visit a person suffering from fever. When I placed my hand upon him, I said: By Allah, I have never seen, till this day, a person running higher temperature than he. Thereupon Allah's Apostle (ﷺ) , turning his face to his companions, said: May I not inform you of a severer temperature than this which these two persons would run on the Day of Resurrection? And they were two hypocrites riding upon the camel turning their back towards (the Muslims).
Explanation & Benefits
Shaykh Maulana Abdul Aziz Alvi
Hadith Commentary: Benefits and Issues: The hypocrites are counted among your companions because they used to recite the testimony of faith (kalimah) and claimed to have faith in you, and the noble Companions (Sahabah) were not aware of their inner reality.
Source: Tuhfat al-Muslim: Commentary on Sahih Muslim, Page: 7042