From the late Fr. John Main in The Present Christ: Further Steps in Meditation (1987):

Meditation is pure action that purifies all our other activities.  It is pure because it is selfless, wholly other-centered.  Most of our activities, our hopes and plans are carried out with a predominant concern for results, for their material worthwhileness.  At its worst this concern is mere self-interest, egoism at its most intense.  But any concern for results, for the fruit of action, betrays a possessiveness or attachment which disturbs the harmony of the energies deployed in the activity.  In meditating day by day, however, humbly and ordinarily, beginning our pilgrimage at the point we have received the gift of faith to begin, wherever that may be, we set out into the mystery of selfless, other-centered activity. We may indeed begin meditating with a superficial concern for results, trying to estimate if our investment of time and energy is justified by returns in knowledge or ‘extraordinary’ experience.  Perhaps anyone formed by our society is conditioned to begin in this way.  But the ordinary practice of meditation purifies us of this spiritual materialism, as we enter into the direct experience of Being, of pure action, we find all our other activities progressively, radically, purified of egoism.  To put this more simply–because meditation leads us into the experience ofl love at the center of our being, it makes us in our ordinary lives and relationships more loving persons.  Meditation teaches us what theology alone found not convince us of, that Being is Love.