When I first heard of Star Wars in Old Norse, I imagined I might be
reading familiar phrases from the movie. This got me thinking what
"Luke, I am your father" (I know that's not an exact quote, but it will
do) would like in ON. Would it be something like the following?

Lukr, ek em faðir þin.

(Admittedly, I invented "Lukr.")

Also, did Old Norse use commas? I know that the normalized texts (or
whatever they are called) use commas, but I am referring to the form in
which the sagas were first written. The reason I am asking is that
English uses commas to set off direct address. Did original ON use
commas similarly, and if not how would they distinguish between two
sentences such as:

I am your father, Luke. (Talking to Luke)

I am your father Luke. (Luke the father is talking)

Thanks.

Rob