Verses with the word pledges in the Old Testament (2 verses):

2 Kings 18:23
Now therefore, I pray thee, give pledges to my lord the king of Assyria, and I will deliver thee two thousand horses, if thou be able on thy part to set riders upon them.

Isaiah 36:8
Now therefore give pledges, I pray thee, to my master the king of Assyria, and I will give thee two thousand horses, if thou be able on thy part to set riders upon them.