What is the ruling on the action of a wife whose brother bought a stolen phone with a SIM card registered in her husband’s name, and then she denied and refused to bear witness to the truth, and even falsely threatened her husband? And is her action considered to be in violation of Allah's حكم (ruling)?

If the wife asks her husband to bear false witness, she has requested a grave evil, for lying and false testimony are forbidden and are among the greatest of major sins. Allah Almighty has commanded bearing witness with truth and justice, even if the testimony is against oneself, one's parents, or one's close relatives, and it is not permissible to conceal or alter it.

If the husband testifies truthfully and does not lie, then there is no blame upon him. As for the wife leaving her home and seeking divorce because her husband refused to bear false witness, this is an act of disobedience (nushooz) and forbidden injustice. The husband must discuss with his wife and explain to her the prohibition of lying and false testimony, and remind her of the obligation to obey her husband and live together with kindness.

If she repents and returns to her home, he should keep her and treat her with kindness. If she insists on seeking divorce, he may refuse to divorce her until she forfeits her dower or a part of it to him.