Quran 49:15 — The Walls (Al-Hujurat)

إِنَّمَا المُؤمِنونَ الَّذينَ ءامَنوا بِاللَّهِ وَرَسولِهِ ثُمَّ لَم يَرتابوا وَجٰهَدوا بِأَموٰلِهِم وَأَنفُسِهِم فى سَبيلِ اللَّهِ ۚ أُولٰئِكَ هُمُ الصّٰدِقونَ

Mu'mens (believers) are those who believe in GOD and His messenger, then attain the status of having no doubt whatsoever, and strive with their money and their lives in the cause of GOD. These are the truthful ones.

[49:14] The Arabs said, "We are Mu'mens (believers)." Say, "You have not believed; what you should say is, 'We are Muslims (submitters),' until belief is established in your hearts." If you obey GOD and His messenger, He will not put any of your works to waste. GOD is Forgiver, Most Merciful.

[49:16] Say, "Are you informing GOD about your religion? GOD knows everything in the heavens and the earth. GOD is Omniscient."