2 Kings 20:4-8

And it happened, before Isaiah had gone out into the middle court, that the word of the Lord came to him, saying,

“Return and tell Hezekiah the leader of My people, ‘Thus says the Lord, the God of David your father: “I have heard your prayer, I have seen your tears; surely I will heal you. On the third day you shall go up to the house of the Lord.

And I will add to your days fifteen years. I will deliver you and this city from the hand of the king of Assyria; and I will defend this city for My own sake, and for the sake of My servant David.” ’ ”

Then Isaiah said, “Take a lump of figs.” So they took and laid it on the boil, and he recovered.

And Hezekiah said to Isaiah, “What is the sign that the Lord will heal me, and that I shall go up to the house of the Lord the third day?”