Ash-Shu'ara 26:13

<h2>Between Musa and Fir`awn</h2><p>Allah tells us what He commanded His servant, son of `Imran and Messenger Musa, peace be upon him, who spoke with Him, to do, when He called him from the right side of the mountain, and conversed with him, and chose him, sent him, and commanded him to go to Fir`awn and his people. Allah says:</p><div class="arabic uthmani">وَإِذْ نَادَى رَبُّكَ مُوسَى أَنِ ائْتَ الْقَوْمَ الظَّـلِمِينَ - قَوْمَ فِرْعَوْنَ أَلا يَتَّقُونَ - قَالَ رَبِّ إِنِّى أَخَافُ أَن يُكَذِّبُونِ - وَيَضِيقُ صَدْرِى وَلاَ يَنطَلِقُ لِسَانِى فَأَرْسِلْ إِلَى هَـرُونَ - وَلَهُمْ عَلَىَّ ذَنبٌ فَأَخَافُ أَن يَقْتُلُونِ </div><p>(And when your Lord called Musa: "Go to the people who are wrongdoers. The people of Fir`awn. Will they not have Taqwa" He said: "My Lord! Verily, I fear that they will deny me, And my breast straitens, and my tongue expresses not well. So send for Harun. And they have a charge of crime against me, and I fear they will kill me.") So, Musa asked Allah to remove these difficulties for him, as he said in Surah Ta Ha:</p><div class="arabic uthmani">قَالَ رَبِّ اشْرَحْ لِى صَدْرِى - وَيَسِّرْ لِى أَمْرِى </div><p>(Musa said: "O my Lord! Open for me my chest. And ease my …

And I shall be embarrassed, and my tongue will not speak plainly, therefor send for Aaron (to help me).

"My breast will be straitened. And my speech may not go (smoothly): so send unto Aaron.

"And my breast straitens, and my tongue expresses not well. So send for Harun (Aaron) (to come along with me).

And I become stressed, and my tongue is not fluent, so send Aaron too.