שמואל א, פרק ד׳, פסוק ו׳

A massive, unexpected roar of joy erupts across the battlefield, breaking the tension between the two warring nations. The echoes of this powerful celebration traveled a great distance, crossing the wide gap that separated the Israelite and Philistine camps, causing immediate astonishment [מלבי״ם].

At first, the Philistines could not understand the reason behind this unusual noise. Confused by the sudden outburst, they began questioning one another to figure out exactly what was happening [מצודת דוד]. As they spoke, they referred to the Israelites as Hebrews, a title that points back to the ancient roots of the nation, recalling how their ancestor Abraham originally came from across the river [מצודת ציון].

The Philistines did not immediately know that the Ark of God had been brought to the front lines. This realization was the result of an active and organized investigation [מלבי״ם, מצודת דוד]. They likely gathered this critical information by sending out spies or by relying on their prior familiarity with Israelite practices [ביאור שטיינזלץ]. Once their inquiry was complete and the rumor was confirmed, the true reality of the situation set in. Knowing that the Ark of God was now present in the enemy camp, the Philistines were completely overcome with fear and trembling [אברבנאל].