Prominent Figures

Catechism of Pius X, 1905 A.D.

3 Q. Are there cases in which it is lawful to kill?
A. It is lawful to kill when fighting in a just war; when carrying out by order of the Supreme Authority a sentence of death in punishment of a crime; and, finally, in cases of necessary and lawful defence of one's own life against an unjust aggressor.
--- Catechism of St. Pius X.

Evangelium Vitae, Encyclical of Pope St. John Paul II, 1995 A.D.

55. This should not cause surprise: to kill a human being, in whom the image of God is present, is a particularly serious sin. Only God is the master of life! Yet from the beginning, faced with the many and often tragic cases which occur in the life of individuals and society, Christian reflection has sought a fuller and deeper understanding of what God's commandment prohibits and prescribes. 43There are in fact situations in which values proposed by God's Law seem to involve a genuine paradox. This happens for example in the case of legitimate defence, in which the right to protect one's own life and the duty not to harm someone else's life are difficult to reconcile in practice. Certainly, the intrinsic value of life and the duty to love oneself no less than others are the basis of a true right to self-defence. The demanding commandment of love of neighbour, set forth in the Old Testament and confirmed by Jesus, itself presupposes love of oneself as the basis of comparison: "You shall love your neighbour as yourself " (Mk 12:31). Consequently, no one can renounce the right to self-defence out of lack of love for life or for self. This can only be done in virtue of a heroic love which deepens and transfigures the love of self into a radical self-offering, according to the spirit of the Gospel Beatitudes (cf. Mt 5:38-40). The sublime example of this self-offering is the Lord Jesus himself.
Moreover, "legitimate defence can be not only a right but a grave duty for someone responsible for another's life, the common good of the family or of the State".44 Unfortunately it happens that the need to render the aggressor incapable of causing harm sometimes involves taking his life. In this case, the fatal outcome is attributable to the aggressor whose action brought it about, even though he may not be morally responsible because of a lack of the use of reason. 45
--- Evangelium Vitae. © Copyright, Libreria Editrice Vaticana.

Saint Augustine of Hippo, City of God, 426 A.D.

"Though defensive violence will always be ‘a sad necessity’ in the eyes of men of principle, it would be still more unfortunate if wrongdoers should dominate just men."

--- City of God, Book IV, Ch. 15

Saint Thomas Aquinas, Summa Theologiae, 1274 A.D.

I answer that, Nothing hinders one act from having two effects, only one of which is intended, while the other is beside the intention. Now moral acts take their species according to what is intended, and not according to what is beside the intention, since this is accidental as explained above (II-II:43:3; I-II:12:1). Accordingly the act of self-defense may have two effects, one is the saving of one's life, the other is the slaying of the aggressor. Therefore this act, since one's intention is to save one's own life, is not unlawful, seeing that it is natural to everything to keep itself in "being," as far as possible. And yet, though proceeding from a good intention, an act may be rendered unlawful, if it be out of proportion to the end. Wherefore if a man, in self-defense, uses more than necessary violence, it will be unlawful: whereas if he repel force with moderation his defense will be lawful, because according to the jurists [Cap. Significasti, De Homicid. volunt. vel casual.], "it is lawful to repel force by force, provided one does not exceed the limits of a blameless defense." Nor is it necessary for salvation that a man omit the act of moderate self-defense in order to avoid killing the other man, since one is bound to take more care of one's own life than of another's. But as it is unlawful to take a man's life, except for the public authority acting for the common good, as stated above (Article 3), it is not lawful for a man to intend killing a man in self-defense, except for such as have public authority, who while intending to kill a man in self-defense, refer this to the public good, as in the case of a soldier fighting against the foe, and in the minister of the judge struggling with robbers, although even these sin if they be moved by private animosity.

--- Saint Thomas Aquinas, Summa Theologiae, II-II, q. 64, a. 7

St Gabriel Possenti.jpg — Saint Gabriel Possenti

From Catholicism.org:
One could not imagine a more unlikely person to be honored as the patron of marksmen than the humble and gentle Saint Gabriel Possenti, also called by Pope Benedict XV, who canonized him, the patron saint of youth. He was given the latter title because he died at the tender age of twenty-four. How he earned the former, we shall explain.
It is somewhat a surprise to discover, in the annals of his life, a unique and almost humorous event that has earned for him the title Patron of marksmen. During the Masonic revolution that was sweeping the Papal States in 1860, bands of brigands, who were somewhat loosely attached to the “army” of Garibaldi, were raiding the villages in their path, looking for plunder, food, and satisfaction for their other unlawful desires. The superior of the Passionist monastery ordered the place locked, and sent all the brothers to the chapel to pray that God deliver the town from this reign of terror. After prayer, Brother Gabriel asked for and received permission to go into the town alone to see what he could do to help. At his arrival, he found that many homes already had been plundered and set afire. There were bands of drunken soldiers hollering and looting and brandishing their pistols. The scene of anarchy was enough to rouse just anger in the gentlest heart.
As he was surveying the horrible scene, Gabriel heard the screams of a young woman being dragged from her home by a drunken soldier. He quickly ran to her aid and, grabbing a pistol from the holster of her assailant, ordered that he leave the town at once, taking all the others with him. Almost immediately a second soldier was commanded to drop his weapons, which the astonished brigand did at once. The cries of the two captives soon brought the sergeant and several other members of his detachment. Seeing the monk now armed with two pistols and obviously in no mood to dialogue, the marauders slowly gathered in front of him, keeping their hands on their pistol grips in case any trouble required the use of them. They were certain this boy monk would be no problem for *them,* the mighty army of the Republic!
The sergeant made a sarcastic remark about a young monk thinking he could stop a whole armed company, but Gabriel merely smiled and told them to lay down their arms so no one would be harmed. Suddenly a small lizard darted onto the street from its secret hiding place some yards away. Instantly Gabriel’s hunting instincts returned and without even so much as a casual aim, the young monk severed the reptile’s head with one perfect shot from the pistol. Again he repeated his request for the men to disarm, a request they fulfilled without further comment. The saintly young brother then demanded that they put out the fires they had started, empty their sacks and pockets of all loot, and march out – all of them – to the end of town. Saint Gabriel escorted them personally, no doubt admonishing them for their misdeeds all the while.
It is clear that Saint Gabriel of the Most Sorrowful Virgin did not hesitate to use his earthly talents to humble the enemies of the Church, and thereby to be God’s answer to his own prayer. For his chilvary in defense of a lady, and for his patriotism in defense of the village (and to his own embarrassment), the grateful townsfolk escorted the monk with prayers and chanting back to the monastery. Two short years later he would be accompanied by his only true Lady to a celestial mansion with the sound of angel voices ringing in his ears.

G.K. Chesterton.jpg — It is alleged against me, and with perfect truth, that I stopped on the way to drink a glass of milk in one shop and to buy a revolver with cartridges in another. Some have seen these as singular wedding-presents for a bridegroom to give to himself, and if the bride had known less of him, I suppose she might have fancied that he was a suicide or a murderer or, worst of all, a teetotaller. They seemed to me the most natural things in the world. I did not buy the pistol to murder myself—or my wife; I never was really modern. I bought it because it was the great adventure of my youth, with a general notion of protecting her from the pirates doubtless infesting the Norfolk Broads, to which we were bound; where, after all, there are still a suspiciously large number of families with Danish names. I shall not be annoyed if it is called childish; but obviously it was rather a reminiscence of boyhood, and not of childhood.

— G. K. Chesterton
*The Autobiography (*44-45)
(Yes G.K. is not a canonized saint, his wisdom does fit this section)

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