Placing God at the center of life and turning to Him during times of deep distress provides profound strength and blessing, especially when a person witnesses His saving response [ביאור שטיינזלץ]. In his time of trouble, David actively sought God [אבן עזרא, ביאור שטיינזלץ]. Even while physically trapped in the hands of his enemies, he pleaded with God from deep within his heart, begging for rescue [רד״ק, מאירי].
Looking at David's escape from the Philistines, one might mistakenly assume his survival was simply the result of his clever trick to act like a madman, rather than an act of Divine intervention. However, the feigned madness was merely the tool God used to answer his prayer and save him. This event served as a direct response to a past question of David's. He had once wondered why madness existed in the world, and God had informed him that a day would come when he would rely on it to survive [אלשיך].
David's deliverance extended far beyond that immediate threat to encompass all his fears and dangers [רש״י, מצודת ציון, ביאור שטיינזלץ]. God rescued him not only from his current enemies but from the ongoing terror of King Saul, who had hurled a spear at him and sent assassins to his home [רד״ק, מאירי]. This constant, sweeping protection from every danger serves as the absolute proof that God Himself is the true source of his salvation. It demonstrates that God rescues him always, even in situations where human tactics, such as pretending to lose his mind, would offer no help at all [אלשיך].