Al-Hāfiz Ibn Hajar—may Allah have mercy on him—said, in his commentary on the aforementioned hadith of Ibn Abbas censuring rhymed prose in supplication: “The instances found in authentic hadiths do not contradict this, because they arose without deliberate intent. This is why they possess such consummate harmony. Examples include the Prophet’s words—may Allah’s blessings and peace be upon him—during battle: ‘O Allah, Revealer of the Book, swift in reckoning, Vanquisher of the Confederates’1; his words—may Allah’s blessings and peace be upon him—‘He fulfilled His promise and made His forces mighty…’—to the end of the hadith2; and his words, ‘I seek refuge in You from an eye that sheds no tears, a soul that is never satisfied, and a heart that does not humble itself.’3 All of these are authentic.”4.
A person who supplicates should avoid grammatical errors, especially when an error alters the meaning, undermines the intended sense, and corrupts what is meant. Correct grammatical inflection is the mainstay of speech: through it the meaning is sound, while without it the meaning becomes defective and corrupt. Indeed, a grammatical error may transform the intended meaning into something false, a forbidden supplication, or the like.
Hence, Abū Uthmān al-Māzinī said to one of his students: “Study grammar, for the Children of Israel fell into disbelief because of a doubled consonant that they pronounced without doubling. Allah—Mighty and Majestic—said to Jesus, ‘Indeed, I caused you to be born—walladtuka.’ But they said, ‘Indeed, I begot you—waladtuka,’ and thus fell into disbelief.”
It is related of al-Asmaʿī that he passed by a man saying in his supplication, “O Dhū al-Jalāl wa-al-Ikrām (O Possessor of Majesty and Honor).” He asked him, “What is your name?” The man replied, “Layth.” Thereupon, he recited: