Does "A Treatise on Affirming Al-Istiwāʾ and Al-Fawqiyyah" by Abu Muhammad Abdullah ibn Yusuf al-Juwayni conform to the methodology of the Ahl al-Sunnah wal-Jama'ah and the Pious Predecessors, and is it permissible to adopt its contents?

The author of this treatise followed the methodology of the Salaf, and its attribution to Abu Muhammad al-Juwayni is not established. Its author mentioned the Hadith of the Ibexes and attributed it to Al-Hafiz Abdul-Ghani al-Maqdisi, who died more than a century after al-Juwayni. The correct attribution is that it was authored by Imam Imad al-Din Abu al-Abbas Ahmad ibn Ibrahim al-Wasiti, who was a companion of Shaykh al-Islam Ibn Taymiyyah and converted to the Madhhab of Imam Ahmad after shifting between various madhahib and sects. This treatise has been published under his name as: (An-Nasiha fi Sifat ar-Rabb Jalla wa 'Ala - Counsel on the Attributes of the Lord, Exalted Be He).