'First Day' in the Bible

From the first day of the seventh month they made a start with the burned offerings, but the base of the Temple of the Lord had still not been put in its place.

For, starting his journey from Babylon on the first day of the first month, he came to Jerusalem on the first day of the fifth month, by the good help of his God.

So those who had come back did so. And Ezra the priest, with certain heads of families, by their fathers' families, all of them by their names, were marked out; and on the first day of the tenth month they took their places to go into the question with care.

And they got to the end of all the men who were married to strange women by the first day of the first month.