Crossing the Jordan River represented a monumental step into a new and unknown reality for the Israelites. To navigate this unfamiliar transition, the nation received precise instructions regarding the physical and spiritual distance they needed to maintain from the Ark of the Covenant leading the way.
A clear boundary was established between the people and the Ark. This separation stemmed primarily from an obligation to preserve the honor of God, as approaching too closely was considered improper and carried potential danger [רש״י, ביאור שטיינזלץ]. The instructions required the people to maintain this boundary from multiple arks. Commentators explain this based on a tradition that two arks actually marched side by side: the Ark of the Divine Presence containing the tablets, and a second ark carrying the bones of Joseph [רש״י, רד״ק, אברבנאל].
The required space between the camp and the arks was set at two thousand cubits, which is roughly one thousand meters. While some view this measurement as a general approximation [אברבנאל], the primary approach among commentators is that it was an exact and strict requirement. This precise measure was already well known to the nation from the time they built the Tabernacle [מצודת דוד, רד״ק, מנחת שי].
There were several reasons for setting this specific distance. On a practical level, it ensured that the entire camp could see their guide. If the people walked too closely, only the front rows would be able to see the Ark. Maintaining a wide gap allowed everyone in the massive camp to keep it in sight, follow a straight path, and avoid crowding or confusion [רד״ק, מלבי״ם]. Furthermore, observing from afar gave the Israelites a broad view of the terrain, allowing them to fully witness and understand the magnitude of the miracle unfolding before them [אברבנאל].
Beyond the practical logistics, the specific measurement of two thousand cubits anticipated future events. Joshua knew that the Israelites would eventually lay siege to the city of Jericho, an operation that would continue through the Sabbath. By establishing a gap of two thousand cubits, which is the exact distance permitted for walking on the Sabbath, he ensured that the people would be legally allowed to walk and pray before the Ark on the day of rest [רש״י, רד״ק, אברבנאל].
The need for such careful guidance was rooted in the fact that the Israelites had never traveled this route before [מצודת ציון]. During the era of Moses, the Ark would travel a distance of three days ahead of the camp to strike fear into their enemies and seek out a resting place. Now, however, its sole purpose was to point out the correct path [מלבי״ם]. Because they were navigating completely uncharted territory, which included crossing a river filled with deep and dangerous sections, the Ark had to go first. It served to mark a safe route through the splitting waters, ensuring the people would not wander helplessly in the unknown [רד״ק, אברבנאל, ביאור שטיינזלץ].