A Commentary, Critical, Practical, and Explanatory on the Old and New Testaments, by Robert Jamieson, A.R. Fausset and David Brown  at sacred-texts.com
1 Kings (1 Samuel) 22:1
sa1 22:1DAVID'S KINDRED AND OTHERS RESORT TO HIM AT ADULLAM. (Sa1 22:1-8)
David . . . escaped to the cave Adullam--supposed to be that now called Deir-Dubban, a number of pits or underground vaults, some nearly square, and all about fifteen or twenty feet deep, with perpendicular sides, in the soft limestone or chalky rocks. They are on the borders of the Philistine plain at the base of the Judea mountains, six miles southwest from Beth-lehem, and well adapted for concealing a number of refugees.
his brethren and all his father's house . . . went down--to escape the effects of Saul's rage, which seems to have extended to all David's family. From Beth-lehem to Deir-Dubban it is, indeed, a descent all the way.
1 Kings (1 Samuel) 22:2
sa1 22:2every one that was in distress--(See on Jdg 11:3).
1 Kings (1 Samuel) 22:3
sa1 22:3David went thence to Mizpeh of Moab--"Mizpeh" signifies a watchtower, and it is evident that it must be taken in this sense here, for it is called "the hold" or fort (Sa1 22:4). The king of Moab was an enemy of Saul (Sa1 14:47), and the great-grandson of Ruth, of course, was related to the family of Jesse. David, therefore, had less anxiety in seeking an asylum within the dominions of this prince than those of Achish, because the Moabites had no grounds for entertaining vindictive feelings against him, and their enmity, to Saul rendered them the more willing to receive so illustrious a refugee from his court.
1 Kings (1 Samuel) 22:5
sa1 22:5the prophet Gad said unto David, Abide not in the hold--This sound advice, no doubt, came from a higher source than Gad's own sagacity. It was right to appear publicly among the people of his own tribe, as one conscious of innocence and trusting in God; and it was expedient that, on the death of Saul, his friends might be encouraged to support his interest.
forest of Hareth--southwest of Jerusalem.
1 Kings (1 Samuel) 22:6
sa1 22:6Saul abode . . . under a tree in Ramah--literally, "under a grove on a hill." Oriental princes frequently sit with their court under some shady canopy in the open air. A spear was the early scepter.
1 Kings (1 Samuel) 22:7
sa1 22:7Hear now, ye Benjamites--This was an appeal to stimulate the patriotism or jealousy of his own tribe, from which he insinuated it was the design of David to transfer the kingdom to another. This address seems to have been made on hearing of David's return with his four hundred men to Judah. A dark suspicion had risen in the jealous mind of the king that Jonathan was aware of this movement, which he dreaded as a conspiracy against the crown.
1 Kings (1 Samuel) 22:9
sa1 22:9DOEG ACCUSES AHIMELECH. (Sa1 22:9-16)
Doeg . . . set over the servants--Septuagint, "the mules of Saul."
1 Kings (1 Samuel) 22:10
sa1 22:10he inquired of the Lord for him--Some suppose that this was a malicious fiction of Doeg to curry favor with the king, but Ahimelech seems to acknowledge the fact. The poor simple-minded high priest knew nothing of the existing family feud between Saul and David. The informer, if he knew it, said nothing of the cunning artifice by which David obtained the aid of Ahimelech. The facts looked against him, and the whole priesthood along with him were declared abettors of conspiracy [Sa1 22:16-17].
1 Kings (1 Samuel) 22:17
sa1 22:17SAUL COMMANDS TO KILL THE PRIESTS. (Sa1 22:17-19)
the footmen that stood about him--his bodyguard, or his runners (Sa1 8:11; Sa2 15:1; Kg1 1:5; Kg1 14:28), who held an important place at court (Ch2 12:10). But they chose rather to disobey the king than to offend God by imbruing their hands in the blood of his ministering servants. A foreigner alone (Psa 52:1-3) could be found willing to be the executioner of this bloody and sacrilegious sentence. Thus was the doom of the house of Eli fulfilled [Sa1 2:30-36].
1 Kings (1 Samuel) 22:19
sa1 22:19Nob, the city of the priests, smote he with the edge of the sword--The barbarous atrocities perpetrated against this city seem to have been designed to terrify all the subjects of Saul from affording either aid or an asylum to David. But they proved ruinous to Saul's own interest, as they alienated the priesthood and disgusted all good men in the kingdom.
1 Kings (1 Samuel) 22:20
sa1 22:20ABIATHAR ESCAPES AND FLEES AFTER DAVID. (Sa1 22:20-23)
one of the sons of Ahimelech . . . escaped--This was Abiathar, who repaired to David in the forest of Hareth, rescuing, with his own life, the high priest's vestments (Sa1 23:6, Sa1 23:9). On hearing his sad tale, David declared that he had dreaded such a fatal result from the malice and intriguing ambition of Doeg; and, accusing himself as having been the occasion of all the disaster to Abiathar's family, David invited him to remain, because, firmly trusting himself in the accomplishment of the divine promise, David could guarantee protection to him.