Musannaf Ibn Abi Shaybah

Hazrat Abu Malik says that the oath for which there is no expiation is when a person deliberately swears a false oath; then it is up to Allah—if He wills, He may punish him, and if He wills, He may forgive him.

Hazrat Sha’bah says that if a person deliberately swears an oath on something, then Hazrat Hammad says there is no expiation (kaffarah) upon him, and Hazrat Hakam says that it is better to pay the expiation.

Ibrahim says that if a person swears an oath about something that it is with him, and he does not know, then he comes to know that it is with him, he says he should offer expiation for the oath. And Hazrat Ata and Hazrat Hakam say regarding that in which expiation is not given, they say he should offer expiation.

Ibrahim says that there are four types of oaths: two require expiation and two do not. "By Allah, I will not do (such and such)" or "By Allah, I will certainly do (such and such)"—these two require expiation. And "By Allah, I did not do (such and such)" and "By Allah, I have already done (such and such)"—these do not require expiation.