It was recorded by Abu Dawood and an-Nasa'i (46). This and its like are obligatory (wajib) because saving an innocent person is mandatory, and it became fixed through the oath, thus it is required; likewise is saving one's own self, such as when the oaths of al-qasamah (oaths for homicide claims) are directed against one in a murder claim, while he is innocent.

The second category is commendable (mandub), which is an oath to which a benefit is attached, such as reconciling between two disputing parties, removing hatred from the heart of a Muslim toward the swearer or another, or averting an evil; this is commendable because performing these matters is encouraged, and the oath is a means leading to them. If one swears to perform an act of obedience or to abandon an act of disobedience, there are two opinions regarding it: One is that it is commendable. This is the opinion of some of our colleagues and the colleagues of al-Shafi'i, because that invites one to perform acts of obedience and abandon acts of disobedience. The second is that it is not commendable, because the Prophet, peace and blessings of Allah be upon him, and his companions did not do this in the vast majority of cases, nor did the Prophet, peace and blessings of Allah be upon him, urge anyone to do it, nor did he encourage it. If that were an act of obedience, they would not have neglected it. Furthermore, this follows the same path as a vow (nadhr), and the Prophet, peace and blessings of Allah be upon him, forbade vows, saying: "It does not bring any good, but rather it is only a means by which to extract from a stingy person." Agreed upon (48).

The third category is the permissible (mubah), such as swearing to perform a permissible act or to abandon one, and swearing to a report about something while one is truthful in it, or thinks he is truthful in it, for Allah, the Almighty, said: {Allah will not impose blame upon you for what is unintentional in your oaths} (49). Among the forms of unintended (laghw) oaths is for one to swear about something he thinks is as he swore it to be (50), and it becomes clear that it is otherwise.