whether a substitute or expiation for an oath is required or not. For al-Bukhārī reports in his Sahīh that the Prophet, peace and blessings be upon him, said:
“Whoever vows to obey Allah should obey Him, and whoever vows to disobey Allah must not disobey Him.”
Whoever thinks that making vows to created beings will bring him benefit or ward off harm is among the misguided, like those who think that worshipping created beings will bring them benefit or ward off harm. Devils may appear to these polytheists, speak to them, carry one of them through the air, inform him of certain matters hidden from him, or bring him money, food, clothing, or other things. Similar things have happened to idol worshippers among Arabs and non-Arabs. Such occurrences are common, both in this age and in others, among misguided innovators who oppose the Quran and Sunnah, either by worshipping someone other than Allah or by practising worship that Allah has not prescribed.
When one of these people displays something extraordinary, it can only be a satanic phenomenon or a fraudulent one. Devils attach themselves to their elite, as happens to some of the intelligent among them. This may also happen to others, but devils attach themselves to people only when some form of religious innovation is present, whether disbelief, wickedness, or ignorance of the revealed law. Satan’s aim is to lead people astray as far as he can. If he can make them disbelievers, he does so; if he can only make them wicked or disobedient, he does so. And if all he can do is diminish their deeds and their religion through an innovation they practise, thereby opposing the revealed law with which Allah sent His Messenger, peace and blessings be upon him, he gains something from them in this way.