All the followers of the various sects of the this Ummah will be in Hell apart from one

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Characteristics of the Victorious Group: Ahl al-Sunnah wa’l-Jamaa’ah
A man accepting Islam can remain married to Christian wife

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Related Answers:
Who are the saved group?
Jamaa’at al-Ahbaash (the Habashis)
If the Qur’an is perfect and complete and contains everything needed for the laws and regulations of sharee‘ah, what need is there for the Sunnah?
Characteristics of the Victorious Group: Ahl al-Sunnah wa’l-Jamaa’ah
A man accepting Islam can remain married to Christian wife

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