Assalaam alaikum,
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Article taken from
Secret Marriage: Is it Valid in Islam?
The minimum conditions for the validity of nikah are the following:
* The consent of the guardian of the woman
* presence of witnesses
* offering and acceptance
* and mahr (dower).
Once the above conditions have been fulfilled, the marriage will be deemed as valid; but if these conditions are not fulfilled, then it will be considered as being null and void.
As far as the consent of guardian is concerned, it can only be dispensed with if the guardian is simply refusing to give consent for considerations other than Islamic, in which case the judge can authorize the marriage after having followed the due process. If, on the other hand, such is not the case and no attempt was made to ascertain the consent of the guardian, then such a marriage would be considered invalid and, therefore, unacceptable in Islam. The Prophet (peace and blessings be upon him) said, "There is no (valid) marriage without a guardian and two reliable witnesses."
By stipulating the above-mentioned conditions for the validity of marriage, Islam insists that a marriage should remain distinct from other loose and immoral lifestyles such as fornication and illicit affairs. Hence, the Prophet insisted on making marriages public.
Based on what has been stated above, the concept of a marriage "just for both of you or for Allah" is not tolerated in Islam.
Society has a share in marriage in the sense that people should know that both of you are married so that they do not suspect you of maintaining an illicit relationship. According to the teachings of Islam, we are under obligation to do whatever we can to safeguard our religion, honor, and dignity; and as such we should stay away not only from that which is considered as strictly haram or forbidden but also from all that is doubtful and dubious. The Prophet (peace and blessings be him) said, "Whosoever shuns what is doubtful he has protected his religion and honor; but whosoever commits what is doubtful, he may inadvertently fall into haram!"
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Wa alaikum salaam