وَإِذَا حُيِّيتُم بِتَحِيَّةٖ فَحَيُّواْ بِأَحۡسَنَ مِنۡهَآ أَوۡ رُدُّوهَآۗ إِنَّ ٱللَّهَ كَانَ عَلَىٰ كُلِّ شَيۡءٍ حَسِيبًا
Waitha huyyeetum bitahiyyatin fahayyoo biahsana minha aw ruddooha inna Allaha kana AAala kulli shayin haseeban
When a (courteous) greeting is offered you, meet it with a greeting still more courteous, or (at least) of equal courtesy. Allah takes careful account of all things.