It happened, when he had made an end of speaking to Saul, that the soul of Jonathan was knit with the soul of David, and Jonathan loved him as his own soul.
It is quite evident here that Jonathan had lost all respect for his father; and he had also doubtless come to appreciate the fact that Saul was no longer fit to be the king of Israel.  Jonathan's action here in bestowing his royal robe and his armor upon David was a symbolical act that indicated Jonathan no longer had any hope or desire of succeeding his father to the throne.  It is also possible that at this time David might have confided in Jonathan the fact of his anointing by the prophet Samuel.