 The love of God for man, calling for a corresponding love of man for God, is his usual theme treated in various ways.One thing particularly worthy of mark is the frequency with which he speaks of the Heart of Christ, and pressingly exhorts every Christian to take the Sacred Heart as an object of special love, veneration and imitation.Indeed, it may perhaps be said that no one before him had laid down and explained so clearly the principles upon which that devotion is grounded, nor had so developed their practical application.