Matthew Poole and continuators on 1 Samuel 20:13

13 The LORD do so, and much more to Jonathan: but if it please my father to do thee evil, then I will shew it thee, and send thee away, that thou mayest go in peace, and the LORD be with thee, as he hath been with my father .

The Lord give thee that Honour and Success in all thy Affairs which he hath given to my Father. Ionathan undoubtedly knew of Samuel's final and irrevocable Sentence of Saul's rejection from the Kingdom, and of the Substitution of some other Person after God's own heart in his stead; and that David was this Person, he might strongly suspect (that which even Saul suspected) both from his eminent Piety; and Wisdom, and Valour, and Universal worth, and from the great things which God had done, both by him, and for him, in preserving and advancing him by such unusual methods; and it is most likely that Ionathan did ask David about it, and that David did Faithfully inform him of the whole truth, as may be gathered both from the words here following, and from chap. 23. 17. And that the knowledge hereof did not raise jealousie, and envy, and rage in him, who was the next Heir of the Crown, as it did in his Father, must be ascribed to Ionathan's Piety towards God, to whose disposal he chearfully submitted himself, and to his sincere Friendship to David, in whose happiness he rejoyced as in his own.