There is a woman living here in Denmark, who is married and has 2 children. She is without residence in Denmark; her husband also lives in Denmark. Now she wants to make a marriage agreement with another man on paper to get a residence permit. Can she do that?

Praise be to Allah, the Lord of the Worlds; and may His blessings and peace be upon our Prophet Muhammad and upon all his Family and Companions.

Islam, with its wisdom, considers the marriage relationship a great relationship, and enshrouded it with a strong fence.  Islam forbids anything that diminishes or decreases this relationship. 

The evidence about this is that it forbids asking a woman for marriage during her waiting period, or even proposing to her indirectly if she is in a revocable divorce, according to the consensus of the scholars.

The matter is more serious if someone wants to conclude another marriage contract with her.  There is no doubt that this is Haram as it is considered as playing and mocking of the rulings of Allah.  Allah Says (interpretation of meaning): {…And treat not the Verses (Laws) of Allâh as a jest,….}[2:231].

Al-Qurtubi said in his interpretation of the above verse, it means not to take the verses of Allah mockingly, as all the verses of Allah are serious.  If anybody mocks of any of His verses, then the above verse of Allah applies to him.

Abu al-Darda said that before the coming of Islam a man would say: 'I divorced my wife, but I did not intend it; I was joking,' that is why this verse was revealed.  Then the Prophet (Sallallahu Alaihi wa Sallam) said: "Whoever divorces, or sets a slave person free, gets married, or marries somebody, and claims that he is joking, he is indeed serious and what he said takes effect."

Therefore, you should not take the initiative to carry out what you are intending to do, whatever the reasons and excuses are, whether on a reality or a false basis.

Allah knows best.