ANSWER:

If they were Christians but were not married at church, they need to renew their marriage.
But if they were atheists, there is no need.

A couple who was living together (only married legally but not religiously)has accepted islam. Do they need to renew/make a new religious marriage in islam.

Fiqh of Marriage | December 1, 2017 4:57 pm
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Shaikh If the marriage is done by saying qabool three times by both he bride and groom as this is a custom in India .. Is the marriage valid ??
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If I declined a marriage offer, then went to sleep then felt really bad that I said no. It was if I really should have given him a chance. Could this be a sign from God that I should say yes. I said yes but due to how he looks I am unsure if I want him. What should I do?