Christians are beginning to lose the spirit of intolerance which animated them: experience has shown the error of the expulsion of the Jews from Spain, and of the persecution of those Christians in France whose belief differed a little from that of the king. They have realized that zeal for the advancement of religion is different from a due attachment to it; and that in order to love it and fulfill its behests, it is not necessary to hate and persecute those who are opposed to it.

[On commence à se défaire parmi les chrétiens de cet esprit d’intolérance qui les animoit : on s’est mal trouvé en Espagne, de les avoir chassés, et en France, d’avoir fatigué des chrétiens dont la croyance différoit un peu de celle du prince. On s’est aperçu que le zèle pour les progrès de la religion est différent de l’attachement qu’on doit avoir pour elle ; et que, pour l’aimer et l’observer, il n’est pas nécessaire de haïr et de persécuter ceux qui ne l’observent pas.]

Charles-Lewis de Secondat, Baron de Montesquieu (1689-1755) French political philosopher

Persian Letters [Lettres Persanes], Letter 60, Usbek to Ibben (1721) [tr. Davidson (1891)]
    (Source)

Referring to the expulsion of Jews from Spain in 1492, and the persecution of the Huguenots (Protestants) in France culminating under Louis XIV in the late 17th Century (and who were still being persecuted while Montesquieu was writing this).

(Source (French)). Alternate translations:

The Christians begin to lay aside that untolerating Spirit, which used to sway them: the Spaniards are sensible how much they have lost by driving the Jews out, and the French by vexing of Christians whose Belief differed a little from that of the Prince. They are now convinced that the Zeal for the Progress of a Religion, is very different form the Devotion she requires; and that to love and observe her, there is no manner of Necessity for hating and persecuting those who do not.
[tr. Ozell (1736), Letter 58]

Christians begin to lay aside that intolerating spirit which formerly influenced them. Spain hath experienced the bad consequence of having expelled the Jews, and France of having worried the Christians, whose faith differed a little from that of the prince. They are nos sensible that a zeal for the progress of religion is different from that attachment which ought to be preserved towards her; and that, in order to love and obey her, it is not necessary to hate and persecute those who do not regard her.
[tr. Floyd (1762)]

Christians are fast losing that spirit of intolerance which formerly animated them: they are beginning to find out that the expulsion of the Jews from Spain was a mistake, and that the persecution of Christians in France whose beliefs differed a little from those of their sovereign was another. They have discovered that fanatic zeal for the advancement of a religion is far different from the attachment which every one ought to feel towards it, and that, in order to love and practise its precepts, it is not necessary to hate and afflict those who refuse to do so.
[tr. Betts (1897)]

The Christians are beginning to lose that spirit of intolerance which animated them. It is now seen that it was a mistake to chase the Jews from Spain, and to persecute French Christians whose belief differed a bit from that of the king. They now perceive that zeal for the expansion of religion is different from dutiful devotion to it, and that love and observance of a religion need not require hatred and persecution of those who do not so believe.
[tr. Healy (1964)]

Christians are beginning to abandon that spirit of intolerance which formerly inspired them; the Spanish regret having banished the Jews, and the French regret having persecuted Christians whose beliefs differed slightly from those of their monarch. They have realized that zeal for the advancement of religion is different form the love one should bear it, and that in order to love it, and observe its precepts, there is no need to hate and persecute those who do not do so.
[tr. Mauldon (2008), Letter 58]

The Christians are beginning to abandon that old spirit of religious intolerance; it was a mistake to expel the Jews from Spain, just as it was to persecute the Christians in France whose beliefs differed only slightly from those of their king. They have realized here that zeal for the advancement of one's religion is different from the attachment one ought to have for it, and that to love and observe one's faith, it is not necessary to hate and persecute those who do not observe it.
[tr. MacKenzie (2014)]