In The Spirit of the Disciplines. Dallas Willard writes,

“In service we engage our goods and strengths in the active promotion of the good of others and the causes of God in our world….  Not every act that may be done as a discipline need be done as a discipline.  I will often be able to serve another simply as an act of love and righteousness without regard to how it may enhance my abilities to follow Christ….  But I may also serve another to train myself away from arrogance, possessiveness, envy, resentment, or covetousness.  In that case, my service is undertaken as a discipline for the spiritual life….  Service to others in the spirit of Jesus allows us the freedom of a humility that carries no burdens of appearance.  It lets us be what we are – simply a particularly lively piece of clay who, as servant of God, happens to be here now with the ability to do this good and needful thing for that other bit of clay there.”  (pp 182 – 184)

When might you need to engage in the discipline of service?