"God willed that the passage of the Israelites over Jordan should be miraculous. Joshua commanded the people to sanctify themselves, for upon the morrow the Lord would do wonders among them. At the appointed time, he directed the priests to take up the ark containing the law of God and bear it before the people. “And the Lord said unto Joshua, This day will I begin to magnify thee in the sight of all Israel, that they may know that, as I was with Moses, so I will be with thee.” 4T 157.1"
"And Joshua said unto the people, Sanctify yourselves: for to morrow the Lord will do wonders among you."
The EGW passage directly quotes Joshua 3:5 and provides context for the verse within the narrative of crossing the Jordan River.
"The priests obeyed the commands of their leader and went before the people, carrying the ark of the covenant. The Hebrew hosts took up the line of march and followed this symbol of the divine presence. The wide column filed down the bank of Jordan, and, as the feet of the priests were dipped in the brim of the river, the water was cut off from above, and the volume below rolled on, leaving the bed of the stream dry. The priests passed on, bearing the ark of God, and Israel followed in the rear. Halfway over Jordan the priests were commanded to stand still in the channel of the river till all the Hebrew host had crossed over. This was to impress upon their minds more forcibly the fact that the power which stayed the waters of Jordan was the same that enabled their fathers to cross the Red Sea forty years before. 4T 157.2"
"And it came to pass, when the people removed from their tents, to pass over Jordan, and the priests bearing the ark of the covenant before the people; And as they that bare the ark were come unto Jordan, and the feet of the priests that bare the ark were dipped in the brim of the water, (for Jordan overfloweth all his banks all the time of harvest,) That the waters which came down from above stood and rose up upon an heap very far from the city Adam, that is beside Zaretan: and those that came down toward the sea of the plain, even the salt sea, failed, and were cut off: and the people passed over right against Jericho. And the priests that bare the ark of the covenant of the Lord stood firm on dry ground in the midst of Jordan, and all the Israelites passed over on dry ground, until all the people were passed clean over Jordan."
The EGW passage recounts the events described in Joshua 3:14-17, including the priests carrying the ark, the waters being cut off, and the people crossing on dry ground. It's a clear retelling of the biblical narrative.