It is narrated from Qasim bin Muhammad (may Allah have mercy on him) that a woman came to Abdullah bin Abbas (may Allah be pleased with them) and said, "Indeed, I have made a vow that I will sacrifice my son." So Abdullah bin Abbas (may Allah be pleased with them) said, "Do not slaughter your son, and pay the expiation for your oath." Then an elder who was present with Abdullah bin Abbas (may Allah be pleased with them) said, "How can there be expiation in this case? (This is a vow of disobedience, and that is considered void.)" So Abdullah bin Abbas (may Allah be pleased with them) said, "Indeed, Allah the Exalted has said: «‏‏‏‏الَّذِينَ يُظَاهِرُونَ مِنْكُمْ مِنْ نِسَائِهِمْ» ‏‏‏‏ (58-Al-Mujadila:2) 'Those among you who declare their wives unlawful (by zihar)...' (Zihar is also an act of disobedience), yet Allah has prescribed in it the expiation which you already know."