'Pledge' in the Bible

And he said, I will send thee a kid of the goats from the flock. And she said, Wilt thou give me a pledge, till thou send it?

And he said, What pledge shall I give thee? And she said, Thy signet and thy cord, and thy staff that is in thy hand. And he gave them to her, and came in unto her, and she conceived by him.

And Judah sent the kid of the goats by the hand of his friend the Adullamite, to receive the pledge from the woman's hand: but he found her not.