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I have been with a girl and I am intending to marry her. The only thing is that she is from Sikh religion. It is stated that a Muslim can only marry among the people of the book (Torah, Bible and Qur'an of course). Because they believe in One God. Sikhism came after Islam so there wasn't any restrictions on the marriage between a Sikh and Muslim. They believe in one god also. I will raise my children Muslims, but I want to know if I will be doing a sin by marrying her.