There were many small tribes around the Madinah township. After the immigration of the Prophet to Madinah, these people embraced Islam. But their embracing of Islam was not the result of any deep mental revolution. In the eyes of God, the person who genuinely adopts the faith of Islam is one who discovers Islam as a reality and enshrines it in the depths of his heart. Those who accept the Faith of God in this manner acquire eternal conviction. Their steadfastness is such they are ready to make any sacrifice. One may perform some righteous deed then think it necessary to announce the fact, but such announcement actually has a nullifying effect. A truly righteous deed is one which is done purely for the sake of God. As God Himself knows everything, where is the necessity to advertise it?