In a Saudi TV program, Professor Khalid Al-Mosleh said that a Muslim should not greet a Christian in a way that implied acceptance of infidel holidays, like saying "Merry Christmas." Drawing a distinction between religious and other holidays, he said: "it is better to avoid initiating any congratulatory remark, and if you are being congratulated, you may answer in a way that does not imply approval." His statements were made on November 19, 2014 on Aali TV, the Saudi Education Ministry's TV channel, in a program dealing with Saudis studying abroad.
Khalid Al-Mosleh: "Allah has instructed us to act kindly toward (non-Muslims) who do not fight us and have not driven us from our homes.
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"As for congratulating them... This kindness ordained by Allah must have its limits, of course. This kindness must not get out of control to the point that if they invite me to drink alcohol, I would accept the invitation in order to be kind to them. That's unacceptable.
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"If you congratulate an infidel on something pertaining to his daily life – for example, on promotion, graduation, marriage, or childbirth, or on similar occasions on which people rejoice... When it comes to congratulating them on everyday matters – some scholars say it is prohibited, some say it is reprehensible, and others say that it is permitted. Indeed, that is the truth. It is permitted.
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"There are two types of holidays. One type is the holidays that are related to religion and worship. A Muslim is not allowed to congratulate an infidel on these holidays in a way that would make that infidel think that the Muslim is pleased with his (infidel) religion. There is a consensus among scholars about this.
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"As for congratulating an infidel in a way that does not imply approval of his religion – using so-called courteous phrasing... Some scholars say that this is just as forbidden as the first case, because it might still make the infidel conclude that you approve of his religion. Other scholars – modern ones – believe that there is nothing wrong with that. If you ask me, it is better to avoid initiating any congratulatory remark. But if someone turns to him and says 'Merry Christmas,' for instance, or uses any expression relating to a religious holiday, he may reply: 'Thank you.' He should not rebuke him or quarrel with him, but should answer using an expression that will make the (infidel) know that he is thanking him for his congratulation. But as for initiating a congratulatory remark for a religious holiday, like Christmas or Thanksgiving – holidays that stem from worship... One should avoid initiating a congratulatory remark, and if you are being congratulated, you may answer in a way that does not imply approval. But if we are talking about regular (non-religious) holidays, such as Independence Day, Labor Day, Mother's Day – there is no harm in a person congratulating someone or being congratulated. The same is true of New Year's Eve, and that's the difference between 'Happy New Year' and 'Merry Christmas.'"