'Master' in the Bible

“Moreover, I will deliver the Egyptians into the hand of a cruel master,And a mighty king will rule over them,” declares the Lord God of hosts.

And the people will be like the priest, the servant like his master, the maid like her mistress, the buyer like the seller, the lender like the borrower, the creditor like the debtor.

Now therefore, come make a bargain with my master the king of Assyria, and I will give you two thousand horses, if you are able on your part to set riders on them.

But Rabshakeh said, “Has my master sent me only to your master and to you to speak these words, and not to the men who sit on the wall, doomed to eat their own dung and drink their own urine with you?”

Perhaps the Lord your God will hear the words of Rabshakeh, whom his master the king of Assyria has sent to reproach the living God, and will rebuke the words which the Lord your God has heard. Therefore, offer a prayer for the remnant that is left.’”

Isaiah said to them, “Thus you shall say to your master, ‘Thus says the Lord, “Do not be afraid because of the words that you have heard, with which the servants of the king of Assyria have blasphemed Me.