Ibrahim says that Hazrat Abdullah used to recite { فَامْضُوا إلَی ذِکْرِ اللہِ } in place of { فَاسْعَوْا إِلَی ذِکْرِ اللہِ } in the Holy Qur'an. And he used to say that if I recite it as { فَاسْعَوْا }, I would strive so hard that my sheet would fall off.