'Third Day' in the Bible

and be ready against the third day; for on the third day Yahweh will come down in the sight of all the people on Mount Sinai.

He said to the people, "Be ready by the third day. Don't have sexual relations with a woman."

It happened on the third day, when it was morning, that there were thunders and lightnings, and a thick cloud on the mountain, and the sound of an exceedingly loud trumpet; and all the people who were in the camp trembled.