An-Nisa 4:94

Ya ayyuha allatheena amanooitha darabtum fee sabeeli Allahifatabayyanoo wala taqooloo liman alqa ilaykumu assalamalasta mu/minan tabtaghoona AAarada alhayatiaddunya faAAinda Allahi maghanimukatheeratun kathalika kuntum min qablu famanna AllahuAAalaykum fatabayyanoo inna Allaha kana bimataAAmaloona khabeera

O you who have believed, when you go forth [to fight] in the cause of Allāh, investigate; and do not say to one who gives you [a greeting of] peace, "You are not a believer," aspiring for the goods of worldly life; for with Allāh are many acquisitions. You [yourselves] were like that before; then Allāh conferred His favor [i.e., guidance] upon you, so investigate. Indeed Allāh is ever, of what you do, Aware.

O you who believe, when you go out in the way of Allah, be careful, and do not say to the one who offers you the Salām (salutation), “You are not a believer” to seek stuff of the worldly life. So, with Allah there are spoils in abundance. In the same state you were before; then Allah favored you. So, be careful. Surely, Allah is All-Aware of what you do.