There are some similarities between David's statute and what is true with regards to our service as Christians today, for we too are engaged in a battle. Although our battle is one that is fougt in the spiritual realm, the same principle holds true. The thing that needs to be pointed out is the fact that God's army requires two forms of service.
Any military venture is dependent on both support and battle forces.
The wonderful thing about it is that both services are equally important. This is true in physical warfare. This is just as true in the body of Christ. No one can say that they themselves are not important and no one can say that others are not important. When we fail to realize this truth, the results can be disastrous.