1 Samuel 29:4

And the princes of the Philistines were wroth with him; and the princes of the Philistines said unto him, Make this fellow return, that he may go again to his place which thou hast appointed him, and let him not go down with us to battle, lest in the battle he be an adversary to us: for wherewith should he reconcile himself unto his master? should it not be with the heads of these men?

Cross-references

In 1 Samuel 29:9, Achish relays that the commanders' decision stands, directly continuing the outcome of the suspicion expressed in 29:4.

1 Samuel 14:21 records Hebrews defecting from the Philistines—exactly what the commanders fear David might do, giving historical precedent for their suspicion.

1 Chronicles 12:19 recounts the same event, adding that David was sent away because the commanders feared he would defect—confirming the narrative.

Psalm 56 is set when Philistines seized David in Gath — exactly this situation of David being distrusted and in danger.