It wasnarrated from Wathilah bin Asqa' that the Messenger of Allah(ﷺ)said:
'Offer prayer for everyone who dies, and strive in Jihadunder every chief." (IT)
English reference (IT): Vol. 1, Book 6, Hadith 1525 (IT)
Arabic reference (IT): Book 6, Hadith 1592 (IT)