Caution: Translations of Quran and Ḥadīth may lead to possible misapplications and misinterpretations. This site is intended for students of sacred knowledge that are proficient in comprehending classical Arabic and have a strong foundation in Islamic sciences. Also note that religious injunctions rely on several aspects beyond what one may glean through reading individual aḥādīth.
Qurʾān Bukhārī Muslim Nasāʾī Abū Dāwūd Tirmidhī Ibn Mājah Mālik Aḥmad Dārimī Ḥākim Ibn Ḥibbān Ṭabarānī Nasāʾī's Kubrá Bayhaqī al-Luʾluʾ wa-al-Marjān Ibn Rajab's Fifty Riyāḍ al-Ṣāliḥīn Aḥmad's Zuhd Suyūṭī
quran:43:52 –

Or am I ˹not˺ better than this one who is insignificant and hardly makes himself clear?  

Or, do you perceive, in which case, am I not better than this one, namely, Moses, who is contemptible, feeble and lowly, and who can scarcely speak clearly?, ˹who can scarcely˺ articulate his speech, because of his lisp — which was the result of his ˹accidentally˺ placing a hot coal in his mouth when he was a child.
القرآن:٤٣:٥٢ –

أَمْ أَنَا خَيْرٌ مِنْ هَٰذَا الَّذِي هُوَ مَهِينٌ وَلَا يَكَادُ يُبِينُ  

{أم} تبصرون، وحينئذ {أنا خير من هذا} أي موسى {الذي هو مهين} ضعيف حقير {و يكاد يُبين} يظهر كلامه للثغته بالجمرة التي تناولها في صغره.