Charles Spurgeon Commentary 1 Samuel 20:2

"And he said unto him, Far from it; thou shalt not die: behold, my father doeth nothing either great or small, but that he discloseth it unto me; and why should my father hide this thing from me? it is not so." — 1 Samuel 20:2 (ASV)

And he said unto him, God forbid; thou shalt not die: behold, my father will do nothing either great or small, but that he will shew it me: and why should my father hide this thing from me? it is not so.

One admires Jonathan for defending Saul; he will not believe anything bad of his father. Children should never believe anything evil of their parents unless it is forced upon them; this rule is a part of the command, Honour thy father and thy mother.