Аль-Исра 17:110

The Prophet (s) would often say, ‘O God, O Compassionate One’. So they said, ‘He [Muhammad, s] forbids us to worship more than one god, and yet he calls upon another [god] together with Him [God]’. The following was then revealed: Say, to them: ‘Invoke God or invoke the Compassionate One, that is to say, invoke Him by either of these [Names] or call upon Him by saying, ‘O God! O Compassionate One!’, whichever (ayyan is conditional; mā is extra), in other words, whichever of these two [Names], you invoke, is beautiful — this [predicate, ‘beautiful’] is indicated by the following [statement]), to Him, to the One called by these two [Names], belong the Most Beautiful Names’, these two [Names] being from among them; and they [the other Names] are [the following] as [mentioned] in hadīth: God, there is no god except Him, the Compassionate, the Merciful, the King, the Holy, the Peace, the Securer, the Controller, the Mighty, the Compeller, the Sublime, the Creator, the Maker [out of nothing], the Fashioner, the [ever] Forgiving, the Almighty, the Bestower, the Provider, the Deliverer, the Knower, the Seizer, the Extender, the Lowerer, the Raiser, the Glorifier, the Abaser, the Hearer, the Seer, the Arbiter, the Just, the Subtle, the Aware, the Forbearing, the Tremendous, the Forgiver, the Thankful, the High, the Great, the Preserver, the Conserver, the Reckoner, the Majestic, the Generous, the Watcher, the Responsive, the Embracing, the Wise, the Loving, the Glorious, the Resurrector, the Witnessing, the Truth, the Guardian, the Strong, the Firm, the Patron, the Praiseworthy, the Numberer, the Initiator, the Restorer, the Life-giver, the Death-maker, the Living, the Eternal Sustainer, the Originator, the Magnificent, the One, the Single, the Everlasting Refuge, the Powerful, the Omnipotent, the Advancer, the Deferrer, the First, the Last, the Outward, the Inward, the Ruler, Exalted, the Benign, the Relenting, the Avenger, the Pardoning, the Gentle, Master of the Kingdom, One of Majesty and Munificence, the Equitable, the Gatherer, the Independent, the Availing, the Restrainer, the Harming, the Benefactor, the Light, the Guiding, the Innovator, the Enduring, the Inheritor, the Reasonable, the Patient, as reported by al-Tirmidhī. God, exalted be He, says: And do not be loud in your prayer, when you recite [the Qur’ān] therein, lest the idolaters hear you and curse you, as well as the Qur’ān and the One Who has revealed it; nor be silent, do [not] murmur, therein, so that your companions might [be able to hear it and] benefit [therefrom]; but seek between that, loudness and silence, a, middle, way.