From Sahih Bukhari (Hadith 7458):
Narrated Abu Musa:A man came to the Prophet (ﷺ) and said, "A man fights for pride and haughtiness another fights for bravery, and another fights for showing off; which of these (cases) is in Allah's Cause?" The Prophet (ﷺ) said, "The one who fights that Allah's Word (Islam) should be superior, fights in Allah's Cause." (See Hadith No. 65, Vol)
Reference: Bukhari 7458