The Two Dogs

Dr. Anthony Lillis uses the parable of two dogs fighting inside you: one represents virtue and one represents vice. "Which one wins? The one you feed." Every choice to indulge a disordered appetite feeds the bad dog; every choice for virtue feeds the good one. Your appetites (desires for comfort, pleasure, approval, control) are not evil in themselves -- but they must be ordered toward God or they become chains. (Ep 643)

This parable captures in a single image what the entire Catholic ascetical tradition has taught for two millennia: the choices we make daily either strengthen virtue or strengthen vice. There is no neutral ground. Every small decision is feeding one of the two dogs. St. Paul describes this interior battle with striking honesty: "For I am delighted with the law of God, according to the inward man: but I see another law in my members, fighting against the law of my mind, and captivating me in the law of sin." The Apostle himself experienced the pull of two competing forces within him -- and he knew that the battle required constant vigilance and grace.

The theological foundation for this teaching is the doctrine of original sin and its consequences. As St. Thomas Aquinas explains: "Through the sin of our first parent, his descendants are deprived of grace, and the powers of the soul are left in a manner weakened and disordered, which weakening is called a wounding of nature." The Council of Trent confirms that while free will was "weakened and bent" by the fall, it was "not destroyed." This means we retain genuine freedom to choose -- but the choice is made in the context of disordered appetites that pull us constantly toward vice. The bad dog has a head start, so to speak. It has been fed by the inherited wound of original sin, by our own past choices, and by the culture that surrounds us.

But the good dog has an infinitely more powerful food source: grace. As St. Augustine prayed: "Give what Thou commandest, and command what Thou wilt." God does not merely command virtue and leave us to our own devices. The Council of Trent declares: "God does not command impossibilities, but by commanding admonishes thee to do what thou canst, and to pray for what thou canst not, and aids thee that thou mayest be able." Every act of grace-filled virtue strengthens the good dog. Every sacrament -- especially the Eucharist and Confession -- pours divine life into the soul, nourishing the virtuous tendencies and starving the vicious ones.

St. John of the Cross develops this teaching with rigorous precision in the Ascent of Mount Carmel. He distinguishes between the appetites themselves -- which are natural movements of desire -- and disordered attachments, which are appetites that have escaped the governance of reason and grace. Hunger is natural and good; gluttony is hunger disordered. The desire for rest is natural and good; sloth is rest disordered. The desire for friendship is natural and good; possessiveness and people-pleasing are friendship disordered. The question is never whether you have appetites but whether your appetites are ordered toward God or turned inward upon yourself.

The practical power of the two-dogs parable lies in its honesty about the incremental nature of both virtue and vice. Virtue is not built in a day. Vice is not conquered in a moment. Both grow through repetition. Aquinas teaches that virtues are stable dispositions of the soul acquired through repeated good acts cooperating with grace, while vices are stable dispositions acquired through repeated evil acts. Each feeding strengthens the corresponding dog. This means that the small choices matter enormously. Choosing to pray when you would rather scroll your phone feeds the good dog. Choosing comfort over duty feeds the bad dog. Neither choice seems dramatic in the moment, but over months and years, the cumulative effect is decisive.

The Church Fathers understood this well. St. Augustine writes: "He who made thee without thee, will not justify thee without thee." Grace is essential, but cooperation with grace is also essential. You must choose which dog to feed. The Council of Trent affirms: "The justified person is not assured of final perseverance without a special privilege of God." There is no point at which you can stop feeding the good dog and expect it to remain strong. The spiritual life requires ongoing, daily cooperation with grace -- an unceasing series of choices to feed virtue rather than vice.

St. Francis de Sales offers encouragement for those who find the battle discouraging. He counsels patience with oneself and persistence in small efforts. "Do not lose courage in considering your own imperfections," he writes, "but instantly set about remedying them -- every day begin the task anew." The parable of the two dogs is not meant to terrify but to clarify. Once you understand the dynamic, you can make deliberate choices. You can identify which dog you have been feeding and redirect your daily habits accordingly.

The sacramental life is the primary nourishment for the good dog. Frequent Confession starves the bad dog by cutting off the supply lines of unrepented sin and bringing hidden struggles into the light. The Eucharist feeds the good dog with the very life of Christ -- the most powerful nourishment available to the soul. Daily prayer, the Examen, spiritual reading, and acts of charity all strengthen virtue. Conversely, habitual indulgence of disordered appetites -- even in small matters -- gradually strengthens vice until it becomes deeply ingrained. As Scripture warns: "Wherefore he that thinketh himself to stand, let him take heed lest he fall." And again: "With fear and trembling work out your salvation." The language of vigilance is not accidental -- it reflects the reality that the battle is ongoing and the stakes are eternal.

St. Teresa of Avila, in her description of the early mansions of the Interior Castle, paints a vivid picture of the soul that has not yet learned to discipline its appetites. She describes a soul surrounded by "reptiles and other creatures" -- the disordered attachments and habitual vices that swarm around the person who has not yet begun the work of mortification. The two-dogs parable speaks to exactly this condition: the bad dog is surrounded by allies, and the good dog is outnumbered until grace tips the balance. Teresa's counsel is the same as Lillis's: begin with awareness, proceed with grace, and trust that God provides what you cannot supply on your own.

The question Dr. Lillis asks is deceptively simple but profoundly searching: "Which dog are you feeding?" The honest answer to that question, on any given day, reveals more about your spiritual state than hours of abstract reflection. Answer it honestly today, and you have taken the first step toward feeding the right one. And remember: you do not feed the good dog alone. Christ feeds it with you, in you, and through every grace He offers.