In The Name of Allaah, The Most Merciful, The Bestower of Mercy
Shaikh Rabee Bin Haadi [may Allaah preserve him] said:
[Lofty] manners have far-reaching [good] outcomes and this why Allaah and His Messenger commanded us [to have good manners]. The Messenger [sallal laahu alayhi wasallam] used to apply these good manners when dealing with people – when dealing with his family in his house, [when dealing with] his companions and his adversaries. And even when a Yahoodi greeted the Messenger of Allaah and said: “As-Saamu Alaykum – death be upon you”, so the Messenger replied, “Alaykum- And upon you’’; then Aa’isha said to [the Yahoodi], “Wa Alaykumus Saam Wal la’nah – Death be upon you and the curse of Allaah”; so, the Messenger said, “O Aa’isha! Indeed, Allaah is kind and gentle and He loves kindness and gentleness.’’
Look [at how] the Yahoodi was dealt with kindly and gently. If he sees this kindness and gentleness, it might pull him towards Islaam, or at least these lofty manners will repel a lot of the evil of this Yahoodi, and thus this would make you [more] upright as well as your call to the Religion of Allaah [The Blessed and Exalted].
Marhaban Yaa Taalibal Ilm’ page 88. Abridged and slightly paraphrased