Genesis 15:8

But he said, “Lord God, how can I know that I will possess it?”

“How can I know this?” Zechariah asked the angel. “For I am an old man, and my wife is well along in years.”

Then Gideon said to God, “If You will deliver Israel by my hand, as You said,

Hezekiah had asked Isaiah, “What is the sign that the Lord will heal me and that I will go up to the Lord’s temple on the third day?”

Show me a sign of Your goodness;
my enemies will see and be put to shame
because You, Lord, have helped and comforted me.

“Ask for a sign from the Lord your God—from the depths of Sheol to the heights of heaven.”

Abraham said to his servant, the elder of his household who managed all he owned, “Place your hand under my thigh,

I am standing here at the spring where the daughters of the men of the town are coming out to draw water.

Then he said to Him, “If I have found favor in Your sight, give me a sign that You are speaking with me.

If they say, ‘Wait until we reach you,’ then we will stay where we are and not go up to them.

Mary asked the angel, “How can this be, since I have not been intimate with a man?”

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