Several key thoughts jumped out as I read through today's passage.
1) Just as God lived among the people (Chapter 5 vs 3) and expected them to be "clean"...so he too lives in us and as a result expects us to be "clean".
Now obviously this refers to diseases and infections in the passage, but similar principals apply with sin. Instructions were provided to make sure that anyone who was unclean or had the potential to be unclean, be removed from the camp so as not to infect others. We are forgiven by acceptance of Christ's sacrifice and so are now "clean", but we need to be careful to provide some isolation of ourselves from those that continue to sin. We are in the world, but instructed not to be of the world.
2) When we wrong another individual, we essentially wrong God (we are unfaithful to God). Numbers 5:6:
On the payback portion of the verse, it is not enough to say sorry, and even to make full restitution...we must go above and beyond to right the wrong.
3) We worship a very intelligent God who knows and fully understands us -God takes faithfulness in marriage very seriously.
When I read through this passage at one point I had visions of a cauldron and cooking up a secret potion. God had already stated in Leviticus (20:10) that if a person was unfaithful to their spouse, they would be put to death- so the quick out from being put to death is lying (who would ever know). Yet God has this ceremony where the priest would make bitter water out of Holy water and dust. The priest would then write a curse on special paper and then makes the woman recite the curse as well. He then washes the words off the page and the curse becomes reality if she is lying. Harm comes to her physically and she is essentially shunned / cursed by the people. I mention that God understands us, because he knows our human nature. This "proving ceremony" that he put in place would have re-enforced the sacredness of marriage and the fact that there are no secrets. God expected purity from his people and put procedures in place to ensure purity.
4) Being set aside for God's special purposes, such as the Nazarites, involves personal sacrifice.
The Nazarites chose to make a promise to God, to be used of him, and during that time there were several rules that they were to abide by. There are certainly things in our lives that may hinder us from doing all we can to further God's kingdom. The things God asks us to sacrifice may not be as extreme as the Nazarites, but I should spend time with God asking him to show me areas of my life that I can eliminate, in order to be more effective for him.