[Sherman Logan]

They say “Salamu Alaykum” and respond by saying “Alaykum El Salam” but are unaware that they have borrowed this from Jews’ “Shalom Aleikhem” and the response “Aleikhem Shalom.”

Umm, Arabic and Hebrew are closely related languages. This greeting need not be borrowed, as it could instead be drawn from a common stock.

Does Italian "borrow" from French, or are they both derived from Latin, explaining similarities quite well.

[BykrBayb]

There is also an English translation. How often do we say “Peace be upon you,” or “Upon you be peace?” That is not our custom. It’s a Jewish custom, which the muslims borrowed.