Qualifications for Muslim Marriage Partners

Muslim marriage partners are a man and a woman. It involves not only rights and duties ordained by God but also cause a family to develop as a basic unit of a Muslim society. It also involves social, financial and inheritance issues.
Your marriage may be a life lasting settlement. You need to understand that every contract has some desired results.
What should be the end result of a Muslim marriage contract?
It is reproduction of human beings.
Second, it legalizes the cohabitation of a man a woman and establishes that issues out of this union are legitimate.
Third, a Muslim marriage contract intends to reach the goals enunciated in Quran.
The Muslim marriage partners are bound to respect the agreed terms and conditions and follow limits announced by God.
Can anyone enter a Muslim Marriage Contract?
No!
There are certain requirements to qualify to enter in a Muslim Marriage contract. When you are missing any of them, you disqualify to make a valid Muslim marriage contract.

Age of Marriage

Every law requires contract partners to attain certain level of age before entering any legal marriage. The Muslim marriage partners are required to reach to the age of puberty. It is presumed that before reaching to the age of marriage, you are unable to make independent financial decisions and solve intricate family problems. While discussing treatment of orphans, Quran says:
“Make trial of orphans until they reach the age of marriage; if then ye find sound judgment in them, release their property to them; but consume it not wastefully, nor in haste against their growing up.” (Quran 4:21 Abdullah Yusufali)
This age limit is essential because you need to understand what you are agreeing to. If you are a minor or unable to understand what rights and duties a Muslim marriage can create, you disqualify to be a Muslim marriage partner.
Quran nowhere mentions the exact age of marriage. But in Muslim Marriage jurisprudence it is equated to the age of puberty. Puberty may be presumed on completion of 16 years for females and 18 years for males. However, in many modern Muslim states the age is legislated as 18 years for Muslim marriage partners.

Soundness of Mind

You are surely a person of sound mind…
…But you are responsible to see whether the other party to the marriage contract is also of sound mind. The lunatics can neither handle their financial matters independently nor can solve the
marriage problems. Muslim jurisprudence allows the guardians of such type of people to bind them in marriage contract in good faith.

Free Consent

Understandably, a contract can’t take place unless the contracting parties are not free to give their independent consent. It is not a matter of momentary importance but an issue related to the whole your life. Quran gives the right of choice to the Muslim marriage partners. While addressing men, Quran says:
“Marry women of your choice. (Quran 4:3 Abdullah Yusufali)
And…
“O ye who believe! Ye are forbidden to inherit women against their will.” (Quran 4: 19 Abdullah Yusufali)

The question arises why the both directions are given to men?
The first verse quoted here gives permission to men. However, not only at the time of Muhammad (PBUH) but even before and after him, the males have been dominating any society. Women might have upper hand in some far history but evidential traces are very few. On the other hand the men have been playing decisive role throughout the written history. So God has made it a responsibility of the men to watch for the right of choice for women.
And Hadith is eloquent on free consent of the parties:
“Khansa bint Khidhan who had a previous marriage, related that when her father married her and she disapproved of that, she went to the Messenger of God and he revoked her marriage.” (Bukhari, Ibn Majah)

“A [girl who was not married] came to the Messenger of God and mentioned that her father had married her against her will, so the Prophet allowed her to exercise her choice.” (Abu Da’ud, on the authority of Ibn ‘Abbas)

Religious Difference

Yes, your religion may be a disqualification if you are not a Muslim. There is only one exception to the women from ‘the people of book’. They may become Muslim marriage partners without converting to Islam. Though some classic jurists have expressed their reservations on this permission but no one can declare such a marriage as invalid or void. On the other hand no Muslim woman is allowed to enter into a Marriage contract with a non-Muslim. Such a marriage would be void and invalid.