Genesis 15:8

And he said, Lord Jehovah, how shall I know that I shall possess it?

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

Then Gideon said to God, "If thou wilt deliver Israel by my hand, as thou hast said,

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

Shew me a token for good, that they which hate me may see it, and be ashamed; for thou, Jehovah, hast helped me and comforted me.

Ask for thee a sign from Jehovah thy God; ask for it in the deep, or in the height above.

And Abraham said to his servant, the eldest of his house, who ruled over all that he had, Put thy hand, I pray thee, 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 favor with thee, then show me a sign that it is thou who speakest with me.

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

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

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