Genesis 15:8

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

And Zacharias said to the angel, By what shall I know this? for I am an old man, and my wife far advanced in years.

And Gideon said to God, If thou wilt save Israel by my hand, as thou hast said,

And Hezekiah said to 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 they who hate me may see it, and be ashamed: because thou, LORD, hast helped me, and comforted me.

Ask thee a sign from the LORD thy God; ask it either in the depth, or in the hight above.

And Abraham said to his eldest servant of his house, that ruled over all that he had, Put, I pray thee, thy hand under my thigh:

Behold, I stand here by the well of water; and the daughters of the men of the city come out to draw water:

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

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

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

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