Breaching a Condition after the Nikah

Question

What is the ruling of the Shari‘a on this matter: a man married off his minor daughter on the condition, “I have a son, and you will have to arrange this son’s nikah” — as is customary in India nowadays to make an exchange: someone has a son and a daughter, and another person likewise has the same, and so the one gives his daughter to the other and the other gives his to him. In short, this man married off his daughter on the condition, “If you arrange my daughter’s nikah (?), then I marry my daughter to your son.

Answer

The nikah has taken place validly; now neither the girl nor the girl’s father can annul it. However, by the breach of promise he committed towards the girl’s father he has become sinful; he should not have done so. What is meant by the girl’s father being simple-minded? Is he insane? And in which of his acts does the lack of sense show itself?

Source: Fatawa Mahmudiyya

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