Please read the entire chapter to get context. I’ve only posted the main verses (from KJV).
This is the main verse I see to prove you become Jewish based on your mother. Please add more if you have proof! Prefer Tanakh only verses.
Deuteronomy 7:3-4“Neither shalt thou make marriages with them; thy daughter thou shalt not give unto his son, nor his daughter shalt thou take unto thy son. For they will turn away thy son from following me, that they may serve other gods:…” This verse does not state you get it from your mother. The father is the head of the household; the mother/daughter is not mentioned because she would have no say in the families beliefs. Willing to discuss this further but I don’t think we should create rules from negatives; especially when the negative is inferred.
You are of your fathers seed! Here are two examples from the book of Numbers, willing to post more if needed. Further more, the Bible deals greatly in paternal lineage not maternal.
Numbers 36:6 (reference to Zelophehad’s 5 daughters) “…Let them marry to whom they think best; only to the family of the tribe of their father shall they marry.” Your tribe/lineage is through your father! Does not mention mother. Lastly, this verse would be irrelevant if a Jewish mother automatically made the child Jewish.
Numbers 36:8 (reference to all of Israel) “And every daughter, that possesseth an inheritance in any tribe of the children of Israel, shall be wife unto one of the family of the tribe of her father, that the children of Israel may enjoy every man the inheritance of his fathers.” Wouldn’t the child of a Jewish mother automatically make them a child of Israel? The answer is no, it is the father who determines the nation of their children.