The climax of the conquest of Jericho is achieved through sound rather than conventional weapons. After days of quiet anticipation and silent circling, a coordinated signal merges the blast of the priests' ram's horns with the mighty shout of the entire nation, bringing down the city's formidable physical barriers. The primary approach among commentators is that this decisive signal is a final, drawn-out blast on the ram's horn [ביאור שטיינזלץ]. When the Israelites hear this long, continuous sound, it serves as their cue [מצודת דוד, ביאור שטיינזלץ]. Immediately, the people release a massive shout, allowing the blast of the horn and the roar of the nation to blend together in close succession [מלבי״ם].
Orchestrating this miraculous event at the very first city conquered in the land is intended to send a clear message to the surrounding nations: God fights for Israel, rather than any standard military force. The specific elements of the strategy—circling for seven days, led by seven priests with seven horns—allude to the seven days of creation and the Sabbath. This demonstrates that the conquest of Jericho is a divine act on the scale of the world's creation. Throughout the first six days, the priests only sound short blasts, saving the long, drawn-out sound exclusively for the seventh day.
The reason the people are instructed to remain completely silent and only shout on the seventh day is viewed from a few different perspectives. One approach explains that a loud shout naturally symbolizes victory and conquest, making it appropriate only at the exact moment the wall is meant to fall [אברבנאל]. Alternatively, the shout serves to spiritually awaken the people, urging them to recognize God's wonders. From a more practical standpoint, the silence during the initial days acts as a tactic to avoid drawing the attention of the city's inhabitants, preventing them from noticing the Israelites and throwing stones down from the ramparts [רלב״ג].
As a result of the deafening shout, the city wall collapses directly into itself, crumbling exactly where it stands [רש״י]. This sudden destruction raises a question regarding the fate of Rahab, whose home is built directly into the city wall. If the entire perimeter had fallen, her house would have been destroyed as well, and if her survival involved an additional, distinct miracle, it would have been explicitly recorded. Therefore, it is understood that the collapse does not encompass the entire wall, but only the section directly facing the Israelite camp. Rahab's house is situated on a different side of the city that remains intact. The destroyed section is swallowed into the earth precisely where it stood, leaving only a small remnant above ground to serve as a lasting memorial to the miracle [רד״ק]. Because the wall collapses directly downward, the Israelites do not need to walk around the city searching for gates or entrances. Instead, every person standing around the perimeter can march straight forward from their exact location directly into the city [מצודת דוד, ביאור שטיינזלץ].