1 Samuel 18:18

And David said unto Saul
Surprised at the offer Saul made him, yet not refusing it, but expressing himself with great modesty and humility:

who [am] I?
as to his person, parentage, and employment, mean and despicable, at least in his own eyes, a type of the lowly Jesus, ( Matthew 11:29 ) ;

and what [is] my life?
keeping sheep, for from thence was he taken and advanced; though some think his meaning is, that to hazard his life, as Saul proposed, was not equivalent to such an honour he meant to confer upon him, and that he was ready to do it at all times:

[or] my father's family in Israel;
though in an honourable tribe, and was an honourable family, yet it seems not to be very great, at least was not in David's esteem worthy of such high advancement, as that one of it should be so nearly related to the king; Ben Gersom thinks David has reference to the original of his family, Ruth the Moabitess:

that I should be son in law to the king?
as he would be by marrying his daughter.