وَأَخي هارونُ هُوَ أَفصَحُ مِنّي لِسانًا فَأَرسِلهُ مَعِيَ رِدءًا يُصَدِّقُني ۖ إِنّي أَخافُ أَن يُكَذِّبونِ

And my brother Aaron; he is more fluent in speech than me. So send him with me as a helper to affirm my truth; I fear they will reject me.