Shared ground
The text presents David acting as a borderland raider while he is based in Philistine-controlled space. It explicitly says he and his men attacked three named peoples (Geshurites, Girzites, Amalekites) who had lived in that region for a long time, in an area described as stretching toward Shur and Egypt.
It also explicitly describes the raids as total against the people in the targeted area: David left no men or women alive. Along with killing, the raids functioned as resource capture: he took livestock and portable goods (sheep, oxen, donkeys, camels, clothing). The episode ends by reconnecting David’s campaign to his relationship with Achish: David returned and came back to him.
Where interpretation differs
Some readers take the narrator’s geographic note (“those…inhabitants of the land…of old…to Shur…to Egypt”) as describing all three groups equally; others think it may describe only some of them, with the list functioning more like a cluster of nearby targets.
There is also a real question about why “no survivors” is emphasized here. One reading takes it as the normal brutality of raid warfare in this setting. Another reads it as a strategic choice meant to prevent witnesses from reporting where David had been and what he had done (a concern that becomes clearer in the wider unit).
Why the disagreement exists
The passage is brief, and it explains the “where” more than the “why.” The phrase “those nations” can naturally point backward to the whole list, but it can also be heard as a general comment about longstanding inhabitants in that border zone. Likewise, “struck the land” could mean attacking settlements across an area rather than one single site, which affects how people picture the raids.
What this passage clearly contributes
These verses contribute a frank portrayal of David’s survival strategy during his time as a fugitive living under Philistine protection: he sustains his band through violent raids and plunder, and the narrator does not soften the human cost. The text does not explicitly evaluate David’s actions here; it reports them and ties them to his continuing access to Achish. In the larger story, that link matters because David’s security depends on managing what Achish believes about David’s activities.