Service means the activity of the spiritual life and is the natural offering prompted by love.
God, who is Love, is ever active in the care of His creation, and His desire is that His creatures and especially man, whom He formed in His own image and likeness, should never be idle. In the care and preservation of His creatures God needs the help of none, for He created them in such a way that without His help they could not continue to exist, and He it is who has provided all that is required to satisfy their desires. When you were in fear of death on account of the bitter cold, you saw one lying buried in the snow and at the point of death, you went to him and lifting him on to your shoulders carried him forward, and the efforts you made produced heat in your body which also passed into his, and both he and you were saved, so that in rescuing him you saved your own life. This is the true end of service. No one can live alone and deprived of the help of others.