John Gill Commentary 2 Samuel 9:10

"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." — 2 Samuel 9:10 (ASV)

Thou therefore, your sons, and your servants
Which were many, and whose numbers are after given:

shall till the land for him ;
manure it, plough it, sow it, and reap it:

and you shall bring in [the fruits] ;
the corn, and oil, and wine, the land produces:

that your master's son may have food to eat ;
meaning either Micha, the son of Mephibosheth, since Mephibosheth seems to be distinguished from him, and opposed to him in the next clause: and who would stand in no need of food from any other quarter, being a guest at the king's table continually; or else Mephibosheth, who by this means would have a sufficiency for his son and servants, and in which Ziba's family and servants would have a share:

but Mephibosheth your master's son shall eat always at my table ;
wherefore the land was to be tilled not for him personally, but for his family, and for what uses he should think fit to put the produce of it to:

now Ziba had fifteen sons and twenty servants :
who were enough to cultivate a considerable quantity of land.