Joshua 3:4 in the King James Version
Yet there shall be a space between you and it, about two thousand cubits by measure: come not near unto it, that ye may know the way by which ye must go: for ye have not passed this way heretofore.
Context
3 and they commanded the people, saying, “When you see the ark of the LORD your God’s covenant, and the Levitical priests bearing it, then leave your place and follow it.
4 Yet there shall be a space between you and it of about two thousand cubits by measure—don’t come closer to it—that you may know the way by which you must go; for you have not passed this way before.”
5 Joshua said to the people, “Sanctify yourselves; for tomorrow the LORD will do wonders among you.”