Exodus 3:12

12He said, aBut I will be with you, and this shall be the sign for you, that I have sent you: when you have brought the people out of Egypt, byou shall serve God on this mountain.”

1 Kings 13:3-5

3And he gave ca sign the same day, saying, “This is the sign that the Lord has spoken: ‘Behold, the altar shall be torn down, and the ashes that are on it shall be poured out.’” 4And when the king heard the saying of the man of God, which he cried against the altar at Bethel, Jeroboam stretched out his hand from the altar, saying, “Seize him.” And his hand, which he stretched out against him, dried up, so that he could not draw it back to himself. 5The altar also was torn down, and the ashes poured out from the altar, according to the sign that the man of God had given by the word of the Lord.

2 Kings 19:29

29“And this shall be dthe sign for you: this year eat what grows of itself, and in the second year what springs of the same. Then in the third year sow and reap and plant vineyards, and eat their fruit.

2 Kings 20:9

9And Isaiah said, “This shall be ethe sign to you from the Lord, that the Lord will do the thing that he has promised: shall the shadow go forward ten steps, or go back ten steps?”

Isaiah 7:14

14Therefore the fLord himself will give you a sign. gBehold, the hvirgin shall conceive and bear a son, and shall call his name iImmanuel.
 Immanuel means God is with us

Isaiah 38:7

7This shall be the sign to you from the Lord, that the Lord will do this thing that he has promised:
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