181 By the time David had finished reporting to Saul, Jonathan was deeply impressed with David - an immediate bond was forged between them. He became totally committed to David. From that point on he would be David's number-one advocate and friend. 2 Saul received David into his own household that day, no more to return to the home of his father. 3 Jonathan, out of his deep love for David, made a covenant with him. 4 He formalized it with solemn gifts: his own royal robe and weapons - armor, sword, bow, and belt.
Matthew Henry's Commentary on 1 Samuel 18:1-4
Commentary on 1 Samuel 18:1-5
(Read 1 Samuel 18:1-5)
The friendship of David and Jonathan was the effect of Divine grace, which produces in true believers one heart and one soul, and causes them to love each other. This union of souls is from partaking in the Spirit of Christ. Where God unites hearts, carnal matters are too weak to separate them. Those who love Christ as their own souls, will be willing to join themselves to him in an everlasting covenant. It was certainly a great proof of the power of God's grace in David, that he was able to bear all this respect and honour, without being lifted up above measure.