Is it permissible to refer to Allah Almighty as “O Joy of Worshippers, and O Delight of the Eyes of the Gnostics,” and what is the rule for applying such expressions to Allah Almighty?

The names and attributes of Allah are tawqifiyyah, meaning they can only be established through authentic evidence. However, the door of informing about Allah is wider, so it is permissible to inform about Him with what is correct in meaning, even if it is not explicitly mentioned [in the texts], such as saying "Joy of the Worshippers" or "Refuge of the Frightened," because this describes an action or effect of His, Glorified be He, without being a name for Him. The Permanent Committee and Sheikh Salih Al Ash-Sheikh have permitted supplications such as "Ya Mu'in" (O Helper) and "Ya Ghiyath al-Mustaghithin" (O Succourer of those seeking succour), because the intent behind them is Allah, and it is not necessary for them to be from His Beautiful Names as long as they carry a correct meaning.