31. The 'firm covenant' in this verse refers to marriage. For marriage is a firm covenant of fidelity. It is only because a woman has faith in the firmness of this covenant that she entrusts herself to a man. If a man decides of his own will to break it, he has no right to withdraw the amount he offered his wife by way of bridal-due at the time of entering into that covenant. (See Towards Understanding the Qur'an, vol. I, Surah 2, n. 251.)