Surah 49:15
"The believers are only those who believe in God and His messenger, (and) then have not doubted but struggled with their wealth and their lives in the way of God. Those – they are the truthful.’"
49.15 – The believers are only those who believe in God and His messenger
This verse makes explicit what seems implicit in many parts of the Quran: that “belief” is not a generic kind of “religious faith” but “only” (innamā) specific to Allah and the messenger. See “Allah in the Quran”.
Such “believers” also struggle ( jāhada) with their wealth and their lives in the way of Allah. See “Jihad in the Quran”.
- from The Quran with Christian Commentary: A Guide to Understanding the Scripture of Islam