'On the Third Day' in the Bible

Go back and say to Hezekiah, the ruler of my people, The Lord, the God of David your father, says, Your prayer has come to my ears, and I have seen your weeping; see, I will make you well: on the third day you will go up to the house of the Lord.

And Hezekiah said to Isaiah, What is to be the sign that the Lord will make me well, and that I will go up to the house of the Lord on the third day?