Warding off the insinuating whispers of the Shaytaan
Question

                Sometimes the imaam recites a long soorah and my mind wanders unintentionally. What should I do? Is it permissible for me to repeat some aayahs of the Qur’aan or du’aa’s, or should I listen to the imaam’s reading?
Praise be to Allah.Push away the worldly 
          thoughts that come to you whilst praying as much as you can, and listen 
          to the imaam’s recitation and ponder the meanings of what he is reciting, 
          so that you may benefit from it, avoid letting your thoughts wander 
          and ward off the insinuating whispers of the Shaytaan. Recite al-Faatihah 
          in both the silent and loud prayers (where the recitation is done silently 
          or out loud), and recite another soorah or passage of  the Qur’aan 
          in the silent prayer, focusing on the meaning of the words. Perhaps 
          by this means Allaah will help you to focus your mind and overcome this 
          lack of concentration. It is also prescribed for you to seek refuge 
          with Allaah from the accursed Shaytaan when you face too many insinuating 
          whispers. 
 And 
          Allaah is the source of strength. May Allaah bless our Prophet Muhammad 
          and his family and companions, and grant them peace.