Abdullah bin Rafi' (may Allah have mercy on him) said: When Sayyiduna Abu Ubaydah bin al-Jarrah (may Allah be pleased with him) was struck by the plague of Amwas, he appointed Sayyiduna Mu'adh bin Jabal (may Allah be pleased with him) as his successor. The illness became severe, and the people said: "O Mu'adh, pray to Allah to remove this punishment from us." He said: "It is not a punishment; rather, it is the supplication of your Prophet, the (manner of) death of the righteous before you, and a martyrdom which Allah grants specially to whomever He wills among you."
Hadith Referenceالمعجم الكبير للطبراني / باب الميم / 17499