The body of faithful which comprises the Catholic Church is divided into three parts: the Church Triumphant (souls in heaven), the Church Suffering (souls in purgatory) and the Church Militant (faithful on earth).
-- Catholic Encyclopedia, "The Church"
The Church Militant has been defined as:
"the Christian church on earth, which is supposed to be engaged in a constant warfare against its enemies…"
-- Webster's Revised Unabridged Dictionary (1998)
It is useful to consider the military metaphors contained in such a definition. As Catholics, our lives should not be seen as "business as usual" but warfare — "constant warfare". We are not regular citizens or noncombatants, but soldiers in the war against Satan; a war which has both spiritual and physical dimensions.
All soldiers are called to a particular cause, traditionally the glory of a king, emperor or state. As Catholics soldiers, we are called to fight for the glory of Christ the King and the triumph of His will. We must follow His commandments, receive His sacraments and carry out His directive to convert all nations. While a worldly soldier is concerned with physical warfare, a Christian soldier is involved in a struggle infinitely more important — the spiritual battle for the salvation of souls.
Just as "soldier" and "warfare" take on different meanings in the context of the Church Militant, so does the term "enemy". The only enemy of Christians is and has always been Satan, but because of his powers, he must be fought both internally and externally (or spiritually and naturally). He is our spiritual enemy when we tempts each of us internally and our natural enemy when he works through other men to subvert the will of God. Since, he is capable of deceiving and tempting every person on earth, he can make accomplices or slaves of men without their explicit knowledge. Such men can be referred to as our "human enemies".
This is an important distinction to make because if Satan rather than an individual human is the true enemy, how we face battle and evaluate victory are very different. Unlike worldly soldiers, we are commanded by our Lord to love our enemies.
"But I say to you, Love your enemies: do good to them that hate you: and pray for them that persecute and calumniate you" (Matt. 5:44).
Therefore, we must always seek that which is best for our human enemies — not their worldly comforts or success, but their eternal salvation. This is not to say the only end to our efforts is conversion since a "victory" occurs every time the desires of Satan is thwarted. And since his desires are always opposed to God's will, a victory is also each instance in which His divine will is done. Both Christ and His Mother Mary have repeatedly told their children that all sins (even by non-Catholics) offend their respective Sacred and Immaculate Hearts. Christ's soldiers must fight to prevent any and every such offense, even if the offenders are not converted. Conversion however remains the surest and most effective way to ensure such offensives will not be committed again.
The human enemies of the Church can usually be divided into two groups — public and private enemies. Public enemies openly declare war on and attempt to carry out the destruction of the Faith or the faithful. Historically, such human enemies have included Jews, Muslims, Protestants, Freemasons and Communists.
Private enemies are those who either do not admit to (secret enemies) or do not realize (deluded enemies) their destructive intentions. These are the most difficult enemies to recognize, let alone fight. They are usually outwardly benign or "well-intentioned" people and are comprised mostly of schismatics, heretics, liberals, modernists and humanists. Their ranks include men and women, young and old, clergy and laity who cloak themselves in acts of human charity and prideful piety which only serve to confuse and seduce others. They are enemies of the Church because they spread defiance of God's laws and undermine his Church through heresy, disobedience or indifference.
These are the human enemies Satan puts in our path and how we choose to respond to them is what defines the true soldiers in the Church Militant.
Needless to say, today's Church Militant is plagued with indifference. Too many soldiers of Christ would rather not fight their enemies because the immediate costs in comfort and human respect are too high. When they witness God being insulted through blasphemy, heresy or denial of His law, they are content to remain silent, denying their love for Him. When questioned directly, they may defend God but only in an equivocal way, depending on how much the opinion of the interrogator means to them.
This is not a "constant warfare", it is a surrender! Soldiers don't sit hiding in the bushes, waiting for someone to accidentally discover them before coming out to fight. They know exactly where the battlefield is and go in earnest to join the war effort. Everyone they make contact with knows not only that they are soldiers but that for which they fight.
Since the beginning of time, Satan has successfully used human respect and pride to tempt the faithful into silence and defiance. How many marriages have been destroyed, profanities been committed, children been aborted, blasphemies been encouraged and souls been eternally lost to Satan because people who knew right from wrong kept silent, putting too much value in human respect? They are more worried about being seen as different or "intolerant" or childish in the eyes of sinners than virtuous in the eyes of God. However subtle this brand of "persecution" may be, the struggle between God's will and man's has always existed. It is why Christ told us in the Sermon on the Mount:
"Blessed are they that suffer persecution for justice' sake: for theirs is the kingdom of Heaven. Blessed are ye when they shall revile you, and persecute you, and speak all that is evil against you, untruly, for My sake. Be glad and rejoice for your reward is very great in Heaven. For so they persecuted the prophets that were before you. ... You are the light of the world. A city seated on a mountain cannot be hid. Neither do men light a candle and put it under a bushel, but upon a candlestick, that it may shine to all that are in the house. So let your light shine before men, that they may see your good works, and glorify your Father Who is in Heaven" (Matt. 5:10-12,14-16).
And repeated by St. John Vianney:
"If you want to belong entirely to God you must be prepared to be despised and rejected by the world. Blessed is he, my friends, who belongs to these, and who follows in the footsteps of the Lord with courage and carries his cross with patience. It is only by doing so that we may obtain the happiness of reaching Heaven."
-- Saint John Vianney, "Sermons of the Curé d'Ars" (1901)
Catholic soldiers cannot remain silent in the face of evil and they cannot run from it in hope for better days. We must fight for the Faith at all times, especially when we are facing persecution. Our human enemies need to know that we hold and defend the Truth, even if they hate us for it. The history of Christendom is filled with saints and martyrs who chose torture and death rather than denying Christ or His Church. They could have saved their lives by going along with the popular errors of the day — be it paganism, Freemasonry, Communism or Islam, but they refused and were eternally rewarded. As beautifully expressed in the words of Blessed Sister Marie-Anne Vaillot, a martyr of the French Revolution who refused to take a masonic oath:
"Citizen, not only do we not want to swear to this oath, but we do not even want to appear to have sworn to it. Do not think us so cowardly and attached to the miserable life that you believe us capable of staining our soul and sacrificing it for an oath which we have always detested and still detest. God will not ask us to render an account of the services we could have rendered our neighbor only by swearing an oath that He detests and condemns. If taking that oath is the only way that we can save our lives, we declare that we prefer to die rather than do anything opposed to the love that we have sworn for God."
-- M. Davies, "For Altar and Throne" (1997)
These days, in most Western countries such courage and dedication is almost non-existent, even though the consequences are much less severe. Many Catholics will deny Christ rather than risk feeling "awkward" or "uncomfortable" in the presence of pagans. They care more about what the faithless think of them than what God does. How many Catholics today would be willingly burned at the stake rather than deny their Faith? What's the use of forcing a denial that is gladly and repeatedly welcomed almost every day?
Getting caught up in battles against heretics and abortionists, it's easy and dangerous to lose sight of the supernatural aspect of the conflict. Satan and the powers of darkness are fighting to ruin every mortal soul, especially those devoted to Christ. This battle isn't just between the Catholics and non-Catholics, but between good and evil, Christ and Satan.
As such, the ways we can fall are varied. Not only can we be defeated through our own tendencies toward doubt or indifference, but also by giving into the zeal of the battle. Too often, humble soldiers fighting for the will of God give way to the vices of pride and anger. We must not lose sight of the true enemy (Satan) and the true goal (the triumph of God's will). In fighting one error, we must not fall victim to another.
Since this is a supernatural battle, we must use the supernatural weapons heaven has given to us. The Mother of God has given us the Most Holy Rosary and the Brown Scapular to assist in our mission. We also have the teaching of the Church Fathers and Catechism of Trent which prepare us to recognize error when it is encountered. We have the Holy Sacrifice of the Mass which is hated by Satan above all, so much so that modern times have seen it subjected to his destructive power. We have been given the other sacraments which give us access to the most precious gift of grace, especially the sacrament of Penance.
Above all else, those fighting for the Christ's Church must never neglect regular prayer and sacrifice. To do so is to fall in to the very errors of the naturalists against which we fight. We cannot inadvertently become allies in the propagation of supernatural indifference. For it is only through the mercy of God and in a State of Grace that we will prevail.
For a reminder on how Catholics are called to live their lives and relate to the world, we will always be able to turn to the timeless words of St. Justin Martyr:
"Christians do not differ from other men as to habitat, language or custom. They live among Greeks and barbarians, wherever destiny has put them. They follow local custom in garb and diet and other matters. But their way of life is nonetheless strange and unbelievable to many. They live in their native land, but as sojourners; as citizens they share everything with their fellowmen, yet they are treated as alien; any alien country is homeland to them, and every homeland an alien country. They marry as men do and beget children, but they do not practice abortion. They share tables but not beds. They live in the flesh but not according to the flesh. They dwell on earth but regard heaven as their city. They follow established law but in their way of life, go beyond what the law requires. They love all and everybody persecutes them. No one knows them, while all condemn them; they are put to death and still are very much alive.
To put it all briefly: What the soul is to the body, Christians are to the world. The soul is present in all the body's members; so are Christians in the world's cities. The soul dwells in the body but does not originate from it; Christians live in the world but do not have their origin there. The invisible soul abides in the visible body; Christians are seen as living in the world, but their piety is invisible. On the other hand, the body, though it suffers nothing from the soul, hates it and makes war upon it because it cannot enjoy its pleasures in peace; the world suffers nothing from Christians but hates them because they reject its pleasures.
The soul loves the flesh and members which hate it; so do Christians love those who hate them. The soul is enclosed in the body but it contains the body; Christians must remain in the world as in a prison, but they contain the world. The immortal soul dwells in a mortal home; Christians are pilgrims in a corruptible world while they look forward to heavenly immortality. God has set them in the world as His sentinels and they may not leave their posts."
-- Saint Justin Martyr."How True Christians Relate to the World", from the Letter to Diognetus" (Mid-Second Century)