From here: http://thegospelcoalition.org/blogs/tgc/2012/06/28/the-page-that-changed-my-life-owen-strachan/
God's Trinitarian essence is love. God's purpose in creating a universe in which sin is permitted must be to communicate that love to creatures. The highest or most beautiful love is sacrificial love for the undeserving. Those---ultimately the vast majority of humans---who are given eyes to see that ineffable beauty will be enthralled by it. They will see the beauty of a universe in which unsentimental love triumphs over real evil. They will not be able to view Christ's love dispassionately but rather will respond to it with their deepest affections. Truly seeing such good they will have no choice but to love it. Glimpsing such love, they will be drawn away from their preoccupations with the gratifications of their most immediate sensations. They will be drawn from their self-centered universes. Seeing the beauty of the redemptive love of Christ is the true center of reality, they will love God and all that he has created.