"For ye have not passed this way heretofore." - Joshua 3:4
Sometimes life is surprisingly similar to the conquest of Canaan. (By this I don't mean that I'm surprised about how often I get involved in hand-to-hand combat with my neighbors.) What I mean is that sometimes I find myself in a completely unfamiliar environment, embarking on something new. Sometimes it's getting a new job, or no longer having a job, or moving, or going to a new school. Whatever it is, I often find myself utterly unprepared, sometimes without even a frame of reference.
I imagine that this is exactly how the Israelites felt as they approached the invasion of Canaan. Technically they were "returning" to some kind of ancestral homeland, but these people had never lived there before. In fact, they had probably lived in the desert for most of their lives; it is likely that most of them had never even seen the place they were going to be living soon. In situations like this, it is easy to let fear overtake you and to become frozen by indecision.
This very thing appears to have happened to the Israelites. In Joshua 3, the Israelites leave from Shittim and go to the river, as though they were about to cross, but then they stop there for three days, perhaps frozen by indecision. The Israelites know that the Jordan is their Rubicon: once they cross it, things are never going to be the same again. Their pleasant pastoral lives are about to be replaced by lives of warfare from which there can be no retreat.
However, I think that God must have known how they were feeling at the time and decided to make the transition less scary for them. So, on the fourth day, Joshua sent messengers throughout the camp, telling the Israelites, "When ye see the ark of the covenant of the Lord your God, and the priests the Levites bearing it, then ye shall remove from your place, and go after it." In other words, God is volunteering to be the first one into the unknown. From what we know of God from Exodus, this is not really surprising. God went before the children of Israel into the desert as a pillar of smoky fire, so having his "throne" go before the children of Israel into the Holy Land is only fitting. However, some Israelites may have been unaware that he could do this. In much of the Ancient Near East, gods were seen as beings that only had jurisdiction over certain areas, not over the whole earth. The idea that God could fight the children of Israel's battles in Egypt, in the desert, and on the other side of the Jordan must have been amazing to some people.
But this is not all God does to reassure them: "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." In other words, God tells the children of Israel to maintain enough distance between themselves and the Ark for them to gain some perspective and to tread with confidence in the path of the Ark-bearers. If they had crowded right behind the Ark, the Israelites would have been unaware of the right path, having to walk it with the Ark, but by allowing some distance between themselves and the Ark, it became easier to see the path of the Ark stretching out before them. This perspective allowed the Israelites to know a section of the right path before they began their journey.
Sometimes in life it is easy to rush into things blindly because we feel we have to, and it is true that in many cases we are called upon to venture into the unknown. However, we need not go without perspective. The Son of God has gone before us. Even if we "have not passed this way" before, we know that He has, and seeing His footsteps stretching out before us can help us find the right path.