Chapter on Rules of Janabah and Methods of Purification

As for what was narrated by Muhammad ibn Ali ibn Mahbub, from Ahmad ibn Muhammad, from al-Hasan ibn Mahbub, from al-‘Ala ibn Razin, from Muhammad ibn Muslim, who said: I asked Abu Ja’far عليه السلام: 'Why is it that a woman who sees in her sleep that a man is having intercourse with her in her private area must perform ghusl, but if in wakefulness a man has non-penetrative sexual contact with her, and she ejaculates, she is not required to perform ghusl?' Imam عليه السلام said: 'This is because in her sleep, she sees that the man is having intercourse with her in her private area, and therefore ghusl becomes obligatory upon her. In the other case, the man only has contact with her without penetration, and so ghusl is not obligatory upon her because penetration did not occur. However, if penetration had occurred in wakefulness, then ghusl would have been obligatory for her, whether she ejaculated or not.'"