'Master' in the Bible

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

And thou shalt till the land for him, thou, and thy sons, and thy servants; and thou shalt bring in the fruits , that thy master's son may have bread to eat: but Mephibosheth thy master's son shall eat bread alway at my table. Now Ziba had fifteen sons and twenty servants.

and I gave thee thy master's house, and thy master's wives into thy bosom, and gave thee the house of Israel and of Judah; and if that had been too little, I would have added unto thee such and such things.

And the king said, And where is thy master's son? And Ziba said unto the king, Behold, he abideth at Jerusalem; for he said, To-day will the house of Israel restore me the kingdom of my father.