Al-Qasas 34

وَأَخِى هَٰرُونُ هُوَ أَفْصَحُ مِنِّى لِسَانًا فَأَرْسِلْهُ مَعِىَ رِدْءًا يُصَدِّقُنِىٓ إِنِّىٓ أَخَافُ أَن يُكَذِّبُونِ ﴿٣٤﴾

Waakhee haroonu huwa afsahu minnee lisanan faarsilhu maAAiya ridan yusaddiqunee innee akhafu an yukaththibooni

"And my brother Harun (Aaron) he is more eloquent in speech than me so send him with me as a helper to confirm me. Verily! I fear that they will belie me." The Noble Quran