35. He must not go with us into battle, or he will turn against us during the fighting (1 Samuel 29:4).
David’s scheme to gain the trust of Achish has its limits. Even though he has effectively deceived the Philistine king into believing him an ally, Achish’s men are not fooled. They know David’s heart and fully expect him to turn back to Israel at any opportunity. David isn’t where he belongs and they know it. As such, David’s scheme has reached its limit. The time of decision has come and the right choice is for David to be the man God has called him to be rather than continue his self-designed exile.
Perhaps the point here is that you can’t build the life you want to have if you’re not where you’re supposed to be.