Rabbi Aryeh Lebowitz

It's a normal name

and your father is not around the Torah doesn't know where the Rambam gets this from he says he says it's a tema that he says that and it seems that the Torah fully disagrees with this and he holds that you're even allowed to call somebody else by their name in front of your father which would mean that the person who married a girl with the same name as his mother or the girl who married a guy with the same name as her father would be able to refer to her husband by his name even in front of the father it sounds like from the Torah

The Radvaz on the Rambam also doesn't know where the Rambam got it from, and he writes, that if it's an unusual name, it's going to look like you're calling your father, and that's going to be a Zilusa.

So the Gura says, I have a simple Maramakom for the Rambam, I can tell you where the Rambam got it from.

He got it from Abaye.

Abaye's name was Nachmeni.

Rabbah called him Abaye because his father's name was Nachmeni.

And everyone also called him Abaye except for Rabbah who would call him Nachmeni.

Everyone else called him Abaye just out of covet for Rabbah who raised him.

Because Rabbah was Rabbah bar Nachmeni.

It's a reference to Rashi in Gittin, Davlam, and Dalam Beis that Abaye was called that because he was raised by Rabbah bar Nachmeni even though his real name was Abaye.

And he was later also named after Nachmeni, Rabbah's father.

So that's exactly how that happened.

Which was his real name?

Was Nachman his real name or was Abaye his real name?

How do we pass him?

You have someone else who has the same name as your parents and you're trying to call them.

So Shulchan Aruch writes, He implies that there is no Yisr whatsoever if it's a normal name.

But he also implies that if it's an unusual name, it's Asr ibn Shalom befanim.

That it all depends, normal name or unusual.