Joshua 3:6
And Joshua spake unto the priests, saying, Take up the ark of the covenant, and pass over before the people. And they took up the ark of the covenant, and went before the people. And Joshua spake unto the priests, saying, Take up the ark of the covenant, and pass over before the people. And they took up the ark of the covenant, and went before the people.
At God's appointed time Joshua commanded the priests to take up the ark of the covenant and pass on ahead of the people toward the Jordan. That ark contained God's law and was the symbol of the divine presence going with Israel. The command came after Joshua had called the people to sanctify themselves, because the Lord would do wonders among them on the morrow. God willed that the crossing should be miraculous. The Jordan was then in flood and could not be crossed at the usual fords, so the passage required divine help.
The priests bearing the ark in front of the people went forward before the waters were stopped, and when the river was cut off it displayed God's power over the river and strengthened Israel's faith. Christ Himself, accompanied by heavenly angels, went before the ark, and the waters were cut off before His presence. Christ and the angels then remained with the ark and the priests standing in the riverbed until all Israel had passed over. Four angels continually accompanied the ark to guard it and to carry out the missions connected with it. By this event God began to magnify Joshua in the sight of all Israel, so that they would know He was with Joshua as He had been with Moses.