A majority of Cosmologists currently hold the view that space in infinite. Reality is not our Universe, but MultiVerses that stretch out into infinity. As one voyages one will never meet a sign that say 'Space Ends Here'. If this is so, that there is an infinite amount of worlds/universes, then everything that could happen has happened, ie there is an infinite amount of good and infinite amount of bad. So whatever good we may do will not impact on infinity, good or bad can only impact on the finite.