Genesis 15:8

And he said, Lord GOD, whereby shall I know that I shall inherit it?

And Zacharias said unto the angel, Whereby shall I know this? for I am an old man, and my wife is well advanced in years.

And Gideon said unto God, Wilt thou save Israel by my hand as thou hast said?

And Hezekiah had said unto Isaiah, What shall be the sign that the LORD will heal me and that I shall go up into the house of the LORD the third day?

Show me a token for good that those who hate me may see it and be ashamed because thou, O LORD, hast helped me and comforted me.

Ask a sign of the LORD thy God; ask it either in the depth, or in the height above.

And Abraham said unto his eldest slave of his house, who ruled over all that he had, Put, I pray thee, thy hand under my thigh,

Behold, I stand here by the fountain of water, and the daughters of the men of the city come out for water:

And he said unto him, If now I have found grace in thy sight, then show me a sign that thou hast spoken with me.

If they say thus unto us, Tarry until we come to you, then we will stand still in our place and will not go up unto them.

Then Mary said unto the angel, How shall this be, seeing I know not a man?

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