David and his family’s stay in “Mizpeh of Moab” was only temporary because the prophet Gad directed David to depart for Judah. The Torah prohibited friendly treaties with Moabites (Deuteronomy 23:2–6). As a true prophet of the Lord, Gad’s duty was to help others understand and obey the Torah. If David established such a treaty with the king of Moab, he would violate the Torah and so risk bringing judgment on himself and all who were with him.
Understanding Gad’s directive and his divine authority as God’s prophet, David obediently “David left and went to the forest of Hereth.” Apparently, David’s family and followers also accompanied him to that location. The forest location would have provided excellent protection against large, organized forces that Saul might bring against them. In obeying the Torah—even though it meant leaving a stronghold built by human hands, David would find protection in a far safer stronghold, God Himself (2 Samuel 23:14; Psalm 18:2; 31:3; 144:2).
The prophet Gad appears to have been a member of David’s band of followers. Gad later informed David of punishment for a violation of the Lord’s will (cf. 2 Sam 24:11–14) and also produced archived records of David’s life (1 Chr 29:29), which suggests the prophet had a long tenure of service to David.
In 1 Samuel 22:6–10 Saul, received a report “that David and his men had been discovered.” Of course, Saul is holding a spear in his hand surrounded by men who bow to his authority. The mention of David’s name caused Saul to launch into a half-crazed, paranoid tirade against “all his servants standing around him.” Saul addressed his officials as “men of Benjamin” (1 Samuel 22:7). This may indicate that Saul had given positions of highest authority in his government only to his tribe. Saul may have been appealing to their tribal loyalty as well as to their greed. Saul threatened that they had much to lose if “the son of Jesse”—of Judah, not of Benjamin—became king in his place. Through the use of two rhetorical questions he indicated that a non-family member would not grant them such favors as he had done.
Saul expressed his paranoia that his family members had not been more supportive of his efforts to dispose of this supposed threat of David. Saul believed their inaction amounted to a massive conspiracy against his crown, and proof of this lay in the fact that no one had informed Saul that his own son Jonathan had made “a covenant with the son of Jesse” (1 Samuel 22:8; 1 Samuel 18:3). Their silence proved to him that none of them was concerned about him.