What may be lost on many about this encyclical is the depth that it goes to undermining a variety of positions that have blossomed in the years following the Second Vatican Council...this document is a corrective vision of what it means to say "God love you" and how you and I are to share that love with one another.
Besides the not so subbtle references to libeation theology are the more gentle prodding of those who think they can live a life of devotion without charity or those who think in the name of the church they can carry out charity in a purely humanitarian way.
There is also a steering of the barque of Peter back to the center, reminding all in the Church that the we are Christian because of the love that God has for us and the mission of the Church is to reveal that love to the world.
What does it mean concretely...pray like Blessed Teresa of Calcutta...respond like Teresa of Calcutta to Jesus in your midst--in need. Devotion and charity are connected on the cross as Jesus entrusts Himself to the Father while giving himself completely for our redemption.