I asked Abu’l-Hasan, Ali bin Musa al-Rida, peace be upon him, about the saying of Allah, Exalted and Glorious is He: «So, the one whom Allah wants to guide, He expands his chest to Islam» (6:125). He said: The one whom Allah wants to guide with his faith in this world to His Garden and the House of His Generosity in the Hereafter, He will expand his chest to submission to Allah, trust in Him and tranquility towards what He has promised of His reward until he is assured of Him. Moreover, the one whom He wants to lead astray from His Garden and House of Generosity in the Hereafter due to his disbelief and disobedience to Him in this world, He will make his chest tight, aggravated, until he doubts in his disbelief and his heart is distressed from his belief until he becomes as if he is elevating in the sky. Similarly, Allah makes impurity for those who do not believe.