1 Samuel 27:12 shows Achish believing David's feigned loyalty, which explains why he now orders David to join the Philistine army.

1 Samuel 29:1 continues the same narrative, describing the Philistine army at Aphek — the very gathering mentioned here.

1 Samuel 29:2 describes David and his men marching in the rear with Achish — a specific detail of the army formation from this gathering.

1 Samuel 29:3 records the Philistine commanders' suspicion of David, which arises directly from this gathering.

In 1 Samuel 31:1, the Philistine gathering recorded here leads directly to the battle where Saul and his sons die.

1 Samuel 7:7 records another Philistine gathering against Israel, echoing the recurring threat of Philistine aggression.

1 Samuel 13:5 describes a massive Philistine army gathering, similar to the muster here — both show Philistine military might.

1 Samuel 17:1 recounts the Philistine army assembling before the David and Goliath battle — a parallel gathering of forces.

1 Chronicles 10:1 retells the same Philistine attack on Israel, paralleling the Samuel account of the battle.

Judges 3:1-4 explains that God left Philistines to test Israel — providing background for why they repeatedly gather for war.