وَإِذَا حُيِّيتُم بِتَحِيَّةٖ فَحَيُّواْ بِأَحۡسَنَ مِنۡهَآ أَوۡ رُدُّوهَآۗ إِنَّ ٱللَّهَ كَانَ عَلَىٰ كُلِّ شَيۡءٍ حَسِيبًا ٨٦
Wa idhā ḥuyyītum bitaḥiyyatin faḥayyū biʾaḥsana minhā aw ruddūhā, innallāha kāna ʿalā kulli shayʾin ḥasībā.
And when you are greeted with a greeting, greet [in return] with one better than it or [at least] return it [in a like manner]. Indeed Allāh is ever, over all things, an Accountant.
Translation: Sahih International