Nikah

In Islam, marriage is a legal contract (Literary Arabic: عقد القران ʻaqd al-qirān, " contract"; Urdu: نکاح نامہ‎ / ALA-LC: Nikāḥ-nāmah),(In Persian (Farsi): ازدواج (ezdevāj) (= marriage) and سند ازدواج or عقدنامه (Sǎnǎde ezdevāj; aqd nāmeh) for the certificate), between two people. Both the groom and the bride are to consent to the marriage of their own free wills. A formal, binding contract is considered integral to a religiously valid Islamic marriage, and outlines the rights and responsibilities of the groom and bride. There must be two Muslim witnesses of the marriage contract. Divorce (Arabic: Talaq) can be effected through husband or through khula is permitted and can be issued by both the bride and groom with equal rights as per Islamic laws and Shariah.

In addition to the usual marriage until death or divorce, there is a different fixed-term marriage known as zawāj al-mutʻah ("temporary marriage") permitted only by the Twelver branch of Shia Islam for a pre-fixed period. There is also Nikah Misyar, a non-temporary marriage with the removal of some conditions permitted by some Sunni Muslims, which usually amount to the wife waiving her right to sustenance from her husband.

Nikah (the term for Islamic marriage) literally means "sexual intercourse." Islam is totally opposed to monasticism and celibacy. Marriage is an act of Sunnah in Islam and is strongly recommended.

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Wikipedia