According to the Roman Breviary, Saint John Eudes is the author of devotion to both the Sacred Heart of Jesus and the Immaculate Heart of Mary. His two works on these two devotions are classics. However, he is also a master to the spiritual life; an unknown master. Many are familiar with the works of Saint Bonaventure, Saint Alphonsus Ligouri and Saint Louis de Montfort to name just three of the masters of the spiritual life. And yet, Saint John Eudes has a lot to contribute. Let us consider this from Saint John Eudes in this excellent work: What truth can there be in the claim that we are Christians and adore a crucified God, a God agonizing and dying upon a Cross, a God who for love of us gives up so noble and excellent life, a God Who sacrifices Himself for us every day, before our eyes upon our altars for our salvation, if we are not ready to sacrifice to Him all that we hold dearest in the world, and even life itself, which in any case belongs to Him by all rights? Surely we are not Christians if we are not in these dispositions. Therefore I say, and this will immediately be clear to anyone who gives a little thought to the truths I have outlined, that all Christians ought to be martyrs, if not in actual fact, at least in intention and in will. So true is this, that if they are not martyrs of Jesus Christ, they will be martyrs of Satan. Choose whichever of the two you love more. If you live under the tyranny of sin, you will be a martyr to your self-love and your passions, and consequently a martyr to the devil. But if you desire to be a martyr of Jesus Christ, you must strive to live in the spirit of martyrdom. What is the spirit of martyrdom? It is a spirit that had five excellent attributes: 1.it is the spirit of strength and constancy which fears only God and sin, and cannot be shaken or overthrown, either by promises or threats, by persuasion or violence. 2.It is the spirit of deepest humility, which feels only horror for the vainglory and publicity of the world, and loves contempt and humiliations. 3.It is the spirit of self-mistrust and of most firm confidence in Jesus Christ our Lord, our Strength, in whom all things can be done. 4.If is the spirit of perfect detachment from the world and everything that is in the world. Those who are to sacrifice their lives to God must also sacrifice to Him all else besides. 5.It is the spirit of most burning love for our Lord Jesus Christ, who leads those animated by this spirit to do all and suffer all