'First Day' in the Bible

Naming the light, Day, and the dark, Night. And there was evening and there was morning, the first day.

And still the waters went on falling, till on the first day of the tenth month the tops of the mountains were seen.

And in the six hundred and first year, on the first day of the first month, the waters were dry on the earth: and Noah took the cover off the ark and saw that the face of the earth was dry.