The interrogative particle indicates that a negative answer is expected: Surely thou art not. The σὺ, thou, first in the sentence, is emphatic, and possibly with a shade of contempt.
Our father Jacob
The Samaritans claimed descent from Joseph, as representing the tribes of Ephraim and Manasseh.
Rev., correctly, sons.
Only here in the New Testament. From (τρέφω) to nourish. A general term for whatever is fed or nursed. When used of animals - mostly of tame ones - cattle, sheep, etc. It is applied to children, fowls, insects, and fish, also to domestic slaves, which, according to some, is the meaning here; but, as Meyer justly remarks, “there was no need specially to name the servants; the mention of the herds completes the picture of their nomadic progenitor.”