The Ruling on the Spy

The Shaykh : Therefore, it is obligatory for the one in authority, if he captures a spy who writes to our enemies about our news, to kill him, even if he is a Muslim, because he has spread corruption on earth. Thus, killing the spy, even if he is a Muslim, is obligatory for the one in authority due to the magnitude of his corruption. However, there was a barrier preventing this in that case, which was that the man was from among the people of Badr. For this reason, the Messenger (peace and blessings be upon him) did not say, "Did you not know that he is a Muslim?" He said:
And in this is evidence, yes, that among the specific attributes of the Messenger (peace and blessings be upon him) is that Allah forgave him what came before of his sin and what came after. And this may occur, as I said, for some of the Companions, such as the people of Badr.