avot patriarch fathers - When did Avraham Avinu become Jewish

Avraham Avinu is often called "the first Jew".

When did he become Jewish. Was it when:

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  He recognized G-d?

  
  


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  G-d spoke to him for the first time?

  
  


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  Covenant Between The Parts?

  
  


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  When G-d changed his name?

  
  


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  When he had a circumcision?

  
  


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  When Yitzchok was born?

  
  
  


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  When he passed the 10th and final test?

  
  


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  Some other event in his life?

  
  

Or perhaps he was never Jewish and we just mean that he was the first in what would eventually become the Jewish nation.

Answer

This article from Chabad.org, Was Abraham Jewish? On the Identity of the Pre-Sinai Hebrews, pretty thoroughly discusses this topic.

I'm not sure how to elaborate on it without rewriting the whole article, but after discussing the different times Avraham was chosen by G-d and the Covenants made between G-d and Avraham, one paragraph says:

Accordingly, when we refer to Abraham as the first Jew or convert, it does not mean that he was actually Jewish in the sense that we know today—in the sense of a binding obligation. Rather, he had the technical status of a Noahide, just as any other person of the time (albeit one that was given additional unique commandments such as circumcision, in which he was indeed obligated). It was not until his descendants stood at Mount Sinai and G‑d proclaimed, “You shall be to Me a treasure out of all peoples . . . and you shall be to Me a kingdom of princes and a holy nation,” that we became the Jewish People.

Please read the article for context.