'One' in the Bible

"Oh that there were one among you who would shut the doors, that you might not kindle fire on my altar in vain! I have no pleasure in you," says Yahweh of Armies, "neither will I accept an offering at your hand.

Don't we all have one father? Hasn't one God created us? Why do we deal treacherously every man against his brother, profaning the covenant of our fathers?

Did he not make you one, although he had the residue of the Spirit? Why one? He sought a godly seed. Therefore take heed to your spirit, and let no one deal treacherously against the wife of his youth.

Then those who feared Yahweh spoke one with another; and Yahweh listened, and heard, and a book of memory was written before him, for those who feared Yahweh, and who honored his name.