The nature of human beings is to be inactive unless influenced by some affection: love or hatred, desire, hope, fear, etc. These affections are the “spring of action,” the things that set us moving in our lives, that move us to engage in activities.
When we look at the world, we see that people are exceedingly busy. It is their affections that keep them busy. If we were to take away their affections, the world would be motionless and dead; there would be no such thing as activity…Just as worldly affections are the spring of worldly actions, so the religious affections are the spring of religious actions…
I am bold in saying this, but I believe that no one is ever changed, either by doctrine, by hearing the Word, or by the preaching or teaching of another, unless the affections are moved by these things. No one ever seeks salvation, no one ever cries for wisdom, no one ever wrestles with God, no one ever kneels in prayer or flees from sin, with a heart that remains unaffected. In a word, there is never any great achievement by the things of religion without a heart deeply affected by those things.
ed. Richard J. Foster and James Bryan Smith