What is the authenticity of the hadith: "When Allah finished His creation, He lay down, then raised one of His legs over the other, then said: 'It is not befitting for any of My creation to do this'"? And is it permissible to say such a thing about Allah, the Almighty and Exalted?

The aforementioned hadith has a weak chain of narration (isnad) and a denounced text (munkar al-matn). Muhammad ibn Fulayh and his father are not considered trustworthy by some imams, and 'Ubayd ibn Hunayn did not hear from Qatadah ibn al-Nu'man. Al-Bayhaqi, Ibn Kathir, and Al-Albani have all affirmed its denounced nature, indicating that it might be from the Isra'iliyyat (Judeo-Christian traditions). This hadith contradicts what was narrated by Al-Bukhari and Muslim concerning the Prophet (peace be upon him) being seen lying down in the mosque with one leg over the other, and that 'Umar and 'Uthman used to do that. It has not been authentically reported from Al-Khallal nor Ibn Al-Qayyim that they permitted the saying that Allah raised one of His legs over the other. Rather, they affirmed the authentic hadith: "When Allah finished His creation, He ascended above His Throne." As for the statement of Qadi Abu Ya'la that the chain of narration of the hadith consists of trustworthy narrators, this does not necessarily mean it is authentic, as there could be an error or a discontinuity in the chain.