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Surah 20. Ta-Ha
Ayah 25 - 35
25قَالَ رَبِّ ٱشْرَحْ لِى صَدْرِى
26وَيَسِّرْ لِىٓ أَمْرِى
27وَٱحْلُلْ عُقْدَةً مِّن لِّسَانِى
28يَفْقَهُوا۟ قَوْلِى
29وَٱجْعَل لِّى وَزِيرًا مِّنْ أَهْلِى
30هَـٰرُونَ أَخِى
31ٱشْدُدْ بِهِۦٓ أَزْرِى
32وَأَشْرِكْهُ فِىٓ أَمْرِى
33كَىْ نُسَبِّحَكَ كَثِيرًا
34وَنَذْكُرَكَ كَثِيرًا
35إِنَّكَ كُنتَ بِنَا بَصِيرًا
[25-35] Moses said, "Lord, open my breast for me14 and make my task easy for me, and remove the impediment from my tongue so that people may understand my speech,15 and appoint a counselor for me from my own family, and strengthen my hands by means of Aaron, who is my brother,16 and make him my associate in my work so that we may glorify Thee and remember Thee always. Thou hast always been watching over us."
14That is, Fill my heart with the courage that may enable me to perform the obligations connected with the great Mission of a Messenger, and give me the confidence for its fulfillment. Prophet Moses prayed for this because he realized the grave responsibilities of the great Mission.
15Prophet Moses prayed to Allah for this because he was conscious that he was not a fluent speaker but was slow of speech. He also knew that as a Messenger he would have to be fluent in order to impress Pharaoh and his courtiers. This is confirmed by the Bible (Exodus 4: 10) but the Talmud gives a strange explanation for this impediment in his speech. According to it, when he was a child he burnt his tongue with a live coal to escape punishment from Pharaoh whose crown he had taken off from his head and put it on his own head. The same story has been adopted by many of our commentators though it is absurd on the face of it. Our interpretation is also confirmed by the Qur'an. The tact is, that at first he was not a fluent speaker and Pharaoh had also taunted him on this impediment (XLIII: 52). Prophet Moses realized the same for he said, "My brother Aaron is more fluent than I, so send him with me as a helper, so that he may support me (with his fluent speech)." (XXVIII: 34). Afterwards this impediment in his speech was removed and he was able to deliver very fluent speeches. This tray be testified by his speeches which have been cited both in the Bible and in the Qur'an for they are masterpieces of eloquence and rhetoric.
Above all, it does not stand to reason that Allah should appoint a lisper or a stammerer or a stutterer as His Messenger. That is why the Messengers have always been the best of mankind in regard to their appearance, personality and capabilities for they had to be most impressive both in their appearance and conduct, so that they could not be made the target of ridicule and contempt by the people because of such personal defects as stammering or stuttering.
16Prophet Aaron was three years older than Prophet Moses (Exodus7:7)