'Pledge' in the Bible

And he said, I will send thee a kid 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 bracelets, and thy staff that is in thine hand. And he gave it her, and came in unto her, and she conceived by him.

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