Surah Adh Dhariyat Tafseer

إِذْ دَخَلُوا عَلَيْهِ فَقَالُوا سَلَمًا

قَالَ سَلَامٌ

When they came in to him and said:"Salaman!"

He answered:"Salamun."

وَإِذَا حُيِّيتُم بِتَحِيَّةٍ فَحَيُّواْ بِأَحْسَنَ مِنْهَأ أَوْ رُدُّوهَأ

When you are greeted with a greeting, greet in return with what is better than it, or return it equally. (4:86)

So the Friend of Allah chose a better reply in return for their greeting, implementing Allah's command:Reciprocating the greeting with the term Salamun is stronger than the greeting using the term Salaman.

The three angels; Jibril, Mika'il and Israfil came to Ibrahim in the image of handsome young wonderfully graceful men. This is why Ibrahim said,

قَوْمٌ مُّنكَرُونَ

You are a people unknown to me.

Allah the Exalted said