Ibn Majah

Benefits and Issues:
(1)
By "mistake" is meant that a person intended to do one thing, but unintentionally did it incorrectly; there will be no sin upon him. However, it is necessary to perform the act again in the correct manner, or to make appropriate amends for what was done.

(2)
"Forgetfulness" means that the person performing the act did not remember, for example:
When the time for prayer arrived, he was occupied with some work, due to which there was a delay.
When he became free, he did not remember that he had not performed the prayer; or, after beginning a fast, he ate or drank because he forgot that he was fasting; or, he made a promise to someone, but when the time came to fulfill the promise, he did not remember, so he was unable to fulfill it on time. In such cases, there is no sin for the delay or similar matters.

(3)
If someone is forced to do an unlawful act by being threatened with death, or is compelled to do something he does not wish to do by being threatened with unbearable harm, then the one who is compelled will not be sinful for carrying out that act. The sin of the wrongful act will be upon the one who compelled him, as well as the sin of coercion itself.

(4)
If someone is forced to divorce his wife, and in order to save his life he utters or writes the words of divorce, then the divorce will not take effect, as is explicitly stated in Hadith 2046.