If the human heart has been created for happiness — a happiness which begins here below, on earth, and which is to be found only in God — you have to admit that the path to it can be none other than 'the guard of the heart'. The science of custody of the heart consists in order and struggle, defense and attack, knowledge and decision, renunciation and suffering; but all this aims at happiness and its possession. Guarding the heart means keeping it for God, living in such a way that our heart become where he reigns, that it contain all the loves which are compatible with our state in life, but that all be based harmoniously on the love of God and be ordained to it. Guarding the heart also means loving purely and passionately those whom we ought to love, while excluding the jealousy, envy and restlessness which are sure sources of disorder in love. Guarding the heart means, always, maintaining an order in our love. The science of guarding the heart teaches the Christian to go de...