1 Samuel 22:1
David therefore departed thence, and escaped to the cave Adullam: and when his brethren and all his father’s house heard it, they went down thither to him. David therefore departed thence, and escaped to the cave Adullam: and when his brethren and all his father’s house heard it, they went down thither to him.
This belongs to the history that follows the slaying of Goliath, when Saul kept David with him and would not permit him to return to his father's house. Then the soul of Jonathan was knit with the soul of David, and Jonathan loved him as his own soul. Jonathan and David made a covenant as brethren, and Jonathan gave David his robe and garments together with his sword and bow and girdle. David was entrusted with important responsibilities, yet he preserved modesty and won the affection of the people and of the royal household.
Expelled from Saul's court and pursued by him, David fled to preserve his life into the mountains of Judah to the cave of Adullam. That cave was a stronghold that a small force could hold against a large army. His flight carried him to the mountains and hills and to the caves of the earth.
His brethren and all his father's house went down to him there because they were unsafe at home from Saul's unreasonable suspicions against them on account of their kinship to David. It was also becoming generally known in Israel that God had chosen David as the future ruler. They believed they would be safer with him even as a fugitive in a lonely cave than exposed to the insane madness of a jealous king.
Their coming brought the family together in sympathy and affection after the bitterness of his brothers' earlier distrust. The harmony that replaced discord brought joy to the exile's heart. In that joy he sang of brethren dwelling together in unity. It was there at Adullam that he composed the fifty-seventh psalm.
That low condition as a fugitive stands in direct contrast to his coronation at Hebron. At Hebron he received the highest honor that can be conferred upon man by his fellow man and was consecrated by solemn rite as God's vicegerent. His patient waiting for the Lord through exile ended in the fulfilled promise of God.