I Samuel 20:39 Midrash

וְהַנַּ֖עַר לֹֽא־יָדַ֣ע מְא֑וּמָה אַ֤ךְ יְהֽוֹנָתָן֙ וְדָוִ֔ד יָדְע֖וּ אֶת־הַדָּבָֽר׃

But the lad knew not any thing; only Jonathan and David knew the matter.

Read midrashic interpretation of I Samuel 20:39: and classical rabbinic exegesis.