In the diagram above I have attempted to present a simplistic view of the human functioning and some of the dynamics involved. Note that the spirit has little influence in unbelievers because it has not been regenerated by the Spirit of God and their will does not yield to it. It is God’s plan that we yield our will to the influence of our spirit which, in the believer, is yielded to the Spirit of God. It is through the influence of the Spirit of God that we should interpret or perceive our lives. These perceptions, in turn, influence our will. This is what I have labeled the mental process.
Our emotional process begins with our perceptions of our needs. We are motivated to meet our needs as we perceive them and we will act in ways that attempt to meet these perceived needs. Our actions will lead to our emotions and all of this will lead to new experiences that will again affect our mental process. From a Biblical point of view, we will either be primarily influenced by our spirit and walk according to the Spirit or be primarily influenced by the perceived needs of our self and try to meet them by walking according to the flesh.
Using this model, let us take a more in-depth view of what Proverbs 3:5-8 is telling us. It says that the key to becoming psychologically whole is to have trust or faith in the whole heart (or the entire diagram). Particularly, if we trust God to meet all our needs and to direct our lives, we will yield our will to the direction of the Spirit. If we fill our spirit and mind with God’s truth and refuse to trust our own perceptions of things, we will see life from God’s point of view. If we believe that God loves us and will meet our needs, we will be motivated by appreciation to avoid evil and selfish actions. If we avoid these selfish actions, that result in negative experiences, we will also avoid the unpleasant emotions that they produce. Furthermore, our Godly motivation will result in Godly actions and Godly emotions. These emotions will produce Godly experiences that will result in positive emotions. These verses suggest that following these principles of interaction can only lead to emotional, physical, and psychological health.