Why is Joshua referred to in the Torah as “bin” Nun?

Why is Joshua referred to in the Torah as “bin” Nun?

Question:-  When the Torah mentions the names of the spies, everyone is referred to as “so-and-so ben (son of) so-and-so.” The only exception is Joshua, who is called Joshua “bin” Nun. Why bin and not ben?

Answer:

Nachmanides (Rabbi Moshe ben Nachman, 1195–1270) points out this unusual vocalization, and suggests that the two words should be read together as “binnun.” This name, rooted in the Hebrew word binah, means “the understanding one,” and was accorded to Joshua out of respect for his keen intellectual abilities. Some other explanations that I found:

• The Torah tells us that Joshua was Moses’ student par excellence. “His attendant, Joshua bin Nun, a lad, would not depart from the tent [of study].”

We are taught that one’s students are considered as his children.  Some use this idea to explain why Joshua was called bin Nun. He was Nun’s biological child, but he was, to a certain degree, the son of Moses as well. This “dual parentage” is hinted in the unusual way the Torah refers to his relationship with his biological father.