What does it mean to be spiritually fit? Well, for starters it is not the same as growing in maturity. You can be spiritually mature and be spiritually unfit at the same time. You can also be spiritually immature (young Christian) and still be spiritually fit. It is not simply spiritual growth either. You can have great growth and it may be cancer or be out of proportion to the rest of the body so that one is deformed. If it is not the same as maturity or growth (although closely connected to them), then what is it?
Spiritual fitness is the state of having a vital and abundant faith that flows from vital union with Jesus. It is expressed by a passionate love for God, life-giving relationships with others and being credible witnesses of the God-Sized Gospel of Jesus Christ in the various spheres of influence we find ourselves in. It is a robust, active, trusting, delighting kind of faith in King Jesus. It is "mustard seed" kind of faith that can "move mountains." It is the suffering kind of faith that has counted the cost of being a disciple of Jesus and is willing to sacrifice life and limb and forsake earthly comfort and security if necessary. It is the generous, giving kind of faith that leads with the will to embrace, forgive and share sacrificially with others in need. It is a serving kind of faith that sees others as "better than oneself" and is willing to get on hands and knees to wash others feet. Simply stated, it is Christ-like faith.