Abu Musa Al-Ash'ari (RAA) narrated that The Messenger of Allah (ﷺ) said:
"The one who fights for Allah's word to become Superior, is striving in Allah's Cause." Agreed upon. (FR)
English reference (FR): Book 11, Hadith 1305 (FR)
Arabic reference (FR): Book 11, Hadith 1278 (FR)