'Master's' in the Bible

Then the king called to Ziba, Saul's servant, and said to him, "All that pertained to Saul and to all his house have I given to your master's son.

You shall till the land for him, you, and your sons, and your servants; and you shall bring in [the fruits], that your master's son may have bread to eat: but Mephibosheth your master's son shall eat bread always at my table." Now Ziba had fifteen sons and twenty servants.

I gave you your master's house, and your master's wives into your bosom, and gave you the house of Israel and of Judah; and if that would have been too little, I would have added to you many more such things.

The king said, "Where is your master's son?" Ziba said to the king, "Behold, he is staying in Jerusalem; for he said, 'Today the house of Israel will restore me the kingdom of my father.'"