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:قَالَ رَبِّ اشْرَحْ لِى صَدْرِىوَيَسِّرْ لِى أَمْرِىMusa said:"O my Lord! Open for me my chest. And ease my task for me." (20:25-26) until:قَدْ أُوتِيتَ سُوْلَكَ يمُوسَىYou are granted your request, O Musa! (20:36)وَلَهُمْ عَلَيَّ ذَنبٌ فَأَخَافُ أَن يَقْتُلُونِAnd they have a charge of crime against me, and I fear they will kill me.because he had killed that Egyptian, which was the reason that he left the land of Egypt