First, let me say the Jordan is not a tiny stream. The Israelites would need God's help to cross the river, just like they needed help crossing the Red Sea. To get God's help, they had to follow God's exact instructions. They were to carry the ark of the covenant first. The leaders of the people instructed them not to move until they had seen the ark pass. When they set out behind the ark, there was to be approximately 2000 cubits between them and the ark. The distance may have been symbolic of our inability to be blameless (which would allow us to approach God), or a strategic plan by God. If the Israelites were behind the ark a distance, they would not only have a better view of God's miracle, but they would not have to stop to wait on God to clear the way. Just as God is our leader, the ark, which contained the Mercy Seat on which God sat, was to lead in battle.

Joshua instructs the priests to carry the ark before the people. He instructs them to take the ark to the brink of the Jordan river, then stand still. The following act of God would be a sign from God to the people that He was with Joshua the same way He had been with Moses. Joshua commands the priests exactly as God says, knowing that they cannot win if they disobey God.

The Jordan River is a prominent landmark discussed in this chapter and in the Bible in general. The importance of crossing the Jordan to enter the promised land is the root of the symbolism we now associate with the river.

Joshua addresses the people before they cross. His speech is to remind the Israelites that God is alive and with them. Joshua's assertion that God would drive out the Canaanite nations reads as a hype session before a football game (or similar sport). Joshua was getting the Israelites ready to go into battle which meant reawakening their faith in God, building their confidence, and reassuring them of their eminent victory.

Each of the 12 tribes of Israel were to select one man who would be given a special task which is not revealed until Joshua 4. This task is detailed in the section below called “Memorial Stones.”

Crossing the Jordan tends to be symbolic of entering Heaven, particularly in songs. Songs such as "On Jordan's Stormy Banks" or "Why We Sing," it is clear that the other side of the river (the Promised Land) represents Heaven, but this doesn't quite fit the narrative.[1]

In "Why We Sing," there is a lyric that says "And when we cross that river, to study war no more, we will sing our songs to Jesus, the One whom we adore." Clearly, the inference is that upon crossing the river, the battle is won—the person is in Heaven singing for Jesus. Of course, chronologically, when the Israelites cross the Jordan, the battle hasn't even begun! I think, however, that this prevailing idea endures because of a deeper meaning. The Israelites may have had to fight for Israel, but upon following God's instructions, they were assured victory. Similarly, we are already promised a victory as soon we choose Jesus.

Once the Israelites had crossed, the priests were allowed to cross with the ark. We are then given 3 important details:

1️⃣ First, this moment solidifies Joshua's place as leader. After witnessing this event, the people fear Joshua the same way they feared Moses.

2️⃣ Second, the tribes of Reuben, Gad, and Manasseh are present and thus are keeping their promise to fight with Israel until every tribe has an inheritance.

3️⃣ Lastly, we are given a tally of soldiers from the previously mentioned tribes: 40,000.

We are not told why only 40,000 men from these 2.5 tribes joined the Israelites in war. However, the most logical reason is that the others stay to defend the land, women, and children west of the Jordan.

When Joshua instructs the priests to cross with the ark, they oblige. As soon as they are out of the riverbed, the waters rush bask into place and overflow the banks back to its normal level.

Chapter 4 brings us back to the special task of the 12 representatives chosen in Joshua 3:12. They were to select 12 stones (1 stone per representative) from where the priests stood and carry them into the Promised Land. The rocks would be a memorial of the miracle God performed. When the Israelites' children inquired of the stones, they where supposed to share the memory of God drying a path through the Jordan.

I found Joshua 4:9 to be a bit confusing and subsequently found that it can be interpreted 3 different ways.[2]

To me, the third option doesn't quite make sense. What does it prove if Joshua threw stones in the river, and then the Israelites picked them up to display them? If he put stones in the river and there were already stones in the river, how did they know which ones to grab? If there weren't any stones in the river, then what would be special about the stones Joshua put there? This is why I think options one and two make the most sense.

Likely, this was the fulfillment of the instructions given to Moses in Deuteronomy 27:4-6.

The Israelites cross the Jordan on the 10th day of the 1st month and camp at a place in Gilgal. We are given the date not only to preserve the beginning of the conquest but as a reminder that the Passover was drawing near. It is in this location that Joshua erects the stones to be a memorial. Once again, he reminds them that the significance of the stones is to pass the story down through their children.

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