Religious zeal is the pure, enlightened commitment to the support and progress of religion → that one owes to the Divinity.

Religious zeal is extremely commendable when it is of this sort, full of sweetness and modeled on the example given to us by Jesus Christ, but when zeal is false, blind and persecuting it is the greatest scourge of the world. [1] We must honor the Divinity, and never seek to avenge it. It cannot be said enough that there is nothing on which men are more given to error than with respect to religious zeal . So many passions hide beneath this mask, and it is the source of so many evils, that it has even been said that it would have been better for the good of humankind if it had not been included in the number of Christian virtues. Indeed, the one time it may be laudable, one finds that it is a hundred times criminal in other instances. However opposed to each other this may be, it operates with an equal violence in every type of religion → , and in the various subdivisions of each religion → .

Abdas, Bishop in Persia, during the time of Theodorius the Younger, by his rash zeal , caused a very horrible persecution to arise against the Christians. In Persia they enjoyed full freedom of religion → , when this bishop boldly destroyed one of the temples devoted to the worship fire. The magi complained first to the king, who sent for Abdas; and who, after very gently censoring him, ordered him to rebuild the temple. Abdas did not want to do it, even though the prince told him that if he disobeyed he would cause all the Christian churches to be demolished. He carried out this threat and left the faithful to the mercy of his clergy, who had been pained by the tolerance that the churches were granted and set upon them with great fury. Abdas was the first martyr who died in this encounter; he was, I say, the first martyr, if one can thus call a man who, by his recklessness, exposed the Church to so much misfortune. The Christians, who had already forgotten one of the main aspects of evangelical patience, had recourse to a remedy which caused another flood of blood. They implored Theodorius for assistance, thereby igniting a long war between the Romans and the Persians. It is true that the latter were at a disadvantage, but was it certain that they would not beat the Romans, and that through their victories, the persecution of Christians in Persia would not spread to other branches of the Church? That is what the indiscreet zeal of a single individual can produce. Thirty years was scarcely enough time to exhaust the violence of the persecutors!

Abdas, a mere individual, and a subject of the king of Persia, ruined the good for others; a good all the more privileged, because it was that of the dominant religion → ; it was a poor excuse to say that the temple he would have rebuilt, would have served for idolatry, because it would not have been he who would have used it for that purpose, and he would not have been responsible for the abuses practiced by those to whom it belonged. Furthermore, no one can be exempt from this law of natural ← religion → :

Finally, what comparison was there between the construction of a temple, even without which the Persians would have continued to be idolaters, and the destruction of several Christian churches? The second evil should have been prevented with the first, as the prince left the decision in the hands of the bishop. Such is the effect of reckless zeal . If it can sometimes be excused, it must never be praised, for that would be to give human frailty a tribute which is due only to wisdom. People’s qualities and good intention do not change evil into good.

If we follow the cruel story of the effects of destructive zeal , we will find it filled with so many tragic scenes, so much killing and carnage, that no plague on the earth had ever produced so many disasters.

The annals of the Church are filled with apocryphal features like this, that have so wounded Christianity that it would never have healed, if the hand that founded it did not save it. Read this history well and you will find that the greatest princes of the world had more to fear from the passions of false zeal , than from the weapons of all their enemies.

If every zealot carefully examined his conscience, it would often teach him that what one calls zeal for one’s ← religion → is in the end pride, self-interest, blindness, or malice. A man who follows received ideas that are different from those of another, stands above him in his own judgment; this imaginary superiority excites his pride and his zeal . If this zeal were genuine and legitimate, he would be more animated against a bad citizen than against a heretic, since there are various circumstances which may excuse the latter before the sovereign judge of the world, and not one that can exonerate the other.

I like to see a man zealous for the advancement of good morals, and the common interest of mankind, but when he employs his zeal to persecute those whom he likes to call heterodox, I say of the good opinion that he has of his belief and his piety that the one is vain and the other criminal.

1. Jaucourt borrows the opening of this article from Voltaire. The entry, "Zeal," in his Philosophical Dictionary begins: "This, in ← religion → , is a pure and enlightened attachment to the maintenance and progress of the worship which is due to the Divinity; but when this zeal is persecuting, blind, and false, it becomes the greatest scourage of humanities." The Philosophical Dictionary was published in 1764; the volume of the Encyclopedia in which Jaucourt's article appeared was published the following year, in 1765. For a full translation of Voltaire's article, see Voltaire, A Philosophical Dictionary: From the French of M. de Voltaire , 2d ed. (London: J. and H.L. Hunt, 1824), 6:411–420.

2. “No monstrous creature is bleaker than they, and never did a fiercer plague and object of the god's hatred raise itself from the Stygian waters.”