“The Catholic life is essentially an army in which we all enlisted and swore to defend the treasure of the Faith on the day of our Baptism. All Catholics are soldiers and we must fight against our enemies, who are principally the Devil and our flesh.
“But often our enemies are also the world and our governors, who should lead us to happiness in society. If these men, far from leading us on the path of good, drag us onto the road of iniquity, we are obliged to make resistance against them. In this sense we should understand these words of Jesus Christ: ‘I did not come to bring peace, but the sword;’ and also. ‘Do not fear those who kill the body, but rather fear him who can destroy both body and soul in the fire of Hell.’ For this reason the Apostles answered the Princes who forbade them to preach: ‘We must obey God rather than men.’
“Now then, this resistance can be either active or passive. The martyr who lets himself be cut to pieces rather than deny his Faith resists passively. The soldier who defends the liberty to adore his God on the battlefield actively resists his persecutors.
“Regarding individuals, there are cases where passive resistance is preferable – since the martyr is more perfect. This is the case of priests who walk unarmed on a bloody battlefield assisting the dying, and who, falling at the hands of the enemy, bear the torment without counter-attacking.
“This is also the case for innocent citizens who, for just reasons, do not enter the armed fight and who, nonetheless, are persecuted by the impious populace because of their Faith.
“But martyrdom is not the normal law of war. The martyrs are few; It would be an inanity or, in other words, it would be tempting God to pretend that an entire people should achieve martyrdom.
“The normal law of war has to be active engagement, where the assaulted party counter-attacks the aggressor in the same way the aggression was made.
“When, therefore, a society is aggressed by the one governing it, a defense must soon be articulated. If it is the case of intellectual or moral aggressions, the weapons to be employed must be of the same genre. But when the aggression is of a material order, legal and peaceful means should be employed first. If they do not produce any result, then it is necessary to appeal to other material means.
“It is necessary, we believe, to make another distinction. If the tyrant, even when he oppresses the people and deprives them of some of their liberties, still allows them the essential liberties, such as to adore God, and does not make social life impossible, then one must bear it with patience – above all if the damages of a armed struggle are greater.
“But, if the tyrant attacks essential liberties, if he betrays the country, if he slays, violates and systematically attacks the life and honor of families and all individuals, then an armed defense is a duty of society, a duty which imposes itself on all members of the community.
“To bear a tyrant in these conditions would be to commit the crime of destroying Religion and the Motherland. This obligation exists not only in the case where it is humanly possible to defeat the tyrant, but also in the case where that it is impossible. The reason for this is because the loss of the Faith and national independence is the ruin of society itself. These are evils greater than the death of a large number of citizens. This is precisely what is happening in the case of Mexico.”
(Msgr. José de Jesús Manríquez y Zárate, Bishop of Huejutla, During the Cristeros Civil War)