Is Saying Good Luck Prohibited?
When people say ‘good luck’ and the like, as a kind of supplication for the person to whom it is said, and wishing him well, there is nothing wrong with that, as is obvious. In fact, it is praiseworthy because it is a kind of supplication for good and wishing the Muslims well. But one should not wish or pray for bad luck for a Muslim, because this involves transgression and enmity towards one’s brother in faith.
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