Quran's Tafhim ( explanation)
*106). Since some people had taken an oath prohibiting for themselves the things which He had permitted, God laid down this injunction regarding oaths made inadvertently. The injunction makes it unnecessary to feel bound by the terms of inadvertent oaths, and for which one will not be reproached by God. And if a person had deliberately made an oath which entails sin he should not abide by his oath and should expiate it (see Towards Understanding the Qur'an, vol. I, Surah 2, nn. 243-4; for expiation see Surah 4, n. 125 above).
*107). To be mindful of one's oaths has several meanings. First, one should make proper use of oaths and should not employ them either frivolously or sinfully. Second, when a person takes an oath, he should take care not to forget it lest he be led to break it. Third, when a man deliberately takes an oath regarding something sound in itself he should pay the penalty if he happens to violate it.
*107). To be mindful of one's oaths has several meanings. First, one should make proper use of oaths and should not employ them either frivolously or sinfully. Second, when a person takes an oath, he should take care not to forget it lest he be led to break it. Third, when a man deliberately takes an oath regarding something sound in itself he should pay the penalty if he happens to violate it.