Sayyiduna Imran bin Husain (may Allah be pleased with him) narrates: A Muslim woman was taken captive by the polytheists. They had previously captured a she-camel belonging to the Prophet (peace and blessings be upon him). When the woman saw that those people were heedless, she made a vow that if Allah granted her salvation by allowing her to ride that she-camel, she would sacrifice it. The narrator states: So the woman was saved, she came to Madinah Munawwarah, and then she began to sacrifice the she-camel. The people stopped her from doing so. This matter was mentioned to the Prophet (peace and blessings be upon him), so the Prophet (peace and blessings be upon him) said: You have given it a very bad reward. Then he (peace and blessings be upon him) said: It is not obligatory for a person to fulfill a vow that involves sin, or that concerns something which he does not own.