Hebrew is not another word for Jewish. It’s not being born to a specific bloodline. And it is not just a language to speak. Hebrew is a step you can choose to take; a lifestyle that you can live.
The first time ‘Hebrew’ appears Biblically is in Genesis/Bereshit 14:13, referring to, “Abram the Hebrew.”
‘Hebrew’ is Strong’s number 5680 and means ‘one from beyond’ or ‘one who has crossed over.’ In Hebrew, the word is spelled: עִבְרִי
Crossing over. Hebrew is an action.
Abram was called Hebrew after he left his father’s house, in his home city of Ur. YHWH told him to leave all that was familiar behind. Abram was obedient to YHWH and then was given the title of Hebrew.
What did Abram cross over from? Joshua 24:2 says that his father, Terah, worshipped other gods, and it’s probably safe to say he wasn’t the only member of the community to do so. Abram left the idol worship and crossed over to YHWH.
YHWH wants all of us to become Hebrew. To leave behind society’s norms and the man-made traditions of Judaism and Christianity and to cross over into what the Scriptures actually say.
Abraham wasn't born a Hebrew. He became it when he left his own ways to follow YHWH’s. You can become it too.