David's refuge in Philistine territory was a critical period, and the exact length of his stay has been a subject of careful calculation. The historical record notes a specific duration involving days and four months, sparking different understandings of just how long this exile lasted.
One approach understands the time span quite literally, viewing the extra time as just a few individual days added to the four months. This would mean David's stay lasted four months and exactly two days [רש"י, חומת אנך], or perhaps four months and a few days into the fifth month [רד"ק]. This shorter timeline is based on chronological calculations regarding the reign of King Saul and the death of Samuel. Since David fled to the Philistines only after Samuel passed away, and Saul died shortly thereafter, it is impossible for David to have stayed in exile for a period of years [רש"י, רד"ק].
In contrast, another perspective suggests that the initial period mentioned actually represents a full year [מצודת ציון, ביאור שטיינזלץ]. This aligns with ancient Aramaic translations that describe the time as a year and four months [רד"ק, אברבנאל]. Some even extend this to mean two full years, making the total time two years and four months [אברבנאל]. This view firmly rejects the timeline that shortens Saul's reign and points out a logical flaw in the shorter calculation: if the time only involved a few extra days, the record should have naturally listed the larger four months first, followed by the days. Furthermore, Achish, the king of Gath, later mentions that David had been with him for days or years, which strongly supports the idea of a much longer, multi-year stay [אברבנאל].
A completely different approach resolves the unusual phrasing by looking at geography rather than just time. According to this view, the timeline is divided by location. The initial days refer to a brief period David spent in the city of Gath, while the four months represent the longer time he lived in the city of Ziklag. This geographical split perfectly explains why the shorter period of days was recorded before the longer period of months [מלבי"ם].