Wholeness and balance. A lot of religions and philosophies talk about it, but what does it mean? It means that if we want to function in the physical world we now find ourselves in, but also be prepared for entering the spiritual world when we die, than we have to balance both sides. Sometimes referred to as walking the razors edge, the straight and narrow, the edge of the sword, and other similar images. 
    Some Christians will quickly point out the Jesus said we cannot straddle the fence, we cannot serve God and also serve the material world, especially in the very materialistic form it has taken in modern times, and they are correct, but that is not what I am talking about. 
    Serving God and developing your spirit doesn't mean you have to give up your job and your secular live and join a monastery. You can serve God and develop spiritually, at least to a certain point, while continuing to have a job, a home, and a physical body that you continue to feed and care for. But that doesn't mean that you can serve the opponents of God and spirituality. You have to have balance, but you can't let the worldly powers and the forces of Satan take control of you. Likewise, we have to sometimes keep our spiritual knowledge and beliefs to ourselves in certain situation. We can't start preaching at the office or burning incense in the factory unless we want to loose our job. And it would probably be pointless to do those things in a place that is not spiritually oriented anyway. 
    A tree is often used as a symbol for this balance, and it's a good one. In order for the tree to hold up many branches covered with leaves, it must have an extensive root system holding it to the ground, otherwise a storm is likely to knock it over. Likewise, if a person become too spiritual and doesn't maintain roots in the material world, his physical body and material existence are likely to suffer as a consequence.