Crossover People
The first instruction for their life as crossover people is to follow the Lord.
Only Christ is capable of leading us across the difficult waters, providing the ultimate direction. This is why we need to know His Word and why obedience is so critical. We are claiming the Promised Land. We are following the Leader. We are obedient to His Word. We live in relationship with Him, but we must not let the distinction blur between the creature and the Creator.
Sanctify yourselves
For the Israelites on the edge of the Jordan, I imagine this meant that they would wash themselves with water and practice the ceremonial rites that would make them clean. For us today, this means that we should come afresh to claim the cleansing of the precious blood of Jesus Christ which washes away all sin, all uncleanness. It also means opening ourselves increasingly as the Holy Spirit enables us to be used by God.