She was my firstborn.

她是我的长女。

《柯林斯英汉双解大词典》

Also I will make him my firstborn, higher than the Kings of the earth.

我也要立他为长子，为世上最高的君王。

youdao

Then say to Pharaoh, 'This is what the Lord says: Israel is my firstborn son

你要对法老说：‘耶和华这样说：以色列是我的儿子，我的长子。

youdao

So in Exodus 4:22, Yahweh tells Moses to say to Pharaoh "Thus says the Lord, 'Israel is my firstborn son.

所以在《出埃及记》第四章第22节中，耶和华让摩西告诉法老,“犹太人是我的长子“

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