During David's time in hiding, a remarkable group of warriors from the tribe of Gad separated themselves from the rest of the nation to join him [רש"י]. Their arrival highlights David's unique ability to gather men of high stature even in his most difficult moments. These men were not ordinary soldiers. They were established military commanders who already held key leadership positions in their hometowns before deciding to join his cause [מלבי"ם, ביאור שטיינזלץ].
The numerical descriptions of these men—ranging from a hundred to a thousand—are understood in two distinct ways. One approach views these numbers as a reflection of military rank. The lowest-ranking officer among this elite group commanded a hundred men, while the most senior commanded a thousand. This perspective emphasizes the magnitude of David's influence; it is a testament to his leadership that such senior, respected commanders were willing to abandon their comfortable positions and go into hiding in the desert simply to support him [רלב"ג, ביאור שטיינזלץ].
Alternatively, these numbers reflect their immense physical strength and extraordinary bravery on the battlefield. According to this view, the weakest warrior among them possessed the power to single-handedly chase away a hundred enemies, while the strongest could pursue a thousand. This miraculous combat ability is seen as a direct fulfillment of the biblical blessing that a small number of Israelites would be able to defeat a vast multitude of their enemies [רש"י, מצודת דוד].