I heard the Prophet ﷺ say on the day of the Conquest of Mecca: No Quraishite will be killed hound hand and foot from this day until the Day of judgment. (Using translation from Muslim 1782a)   

سَمِعْتُ رَسُولَ اللَّهِ ﷺ يَقُولُ يَوْمَ فَتْحِ مَكَّةَ «لَا يُقْتَلُ قُرَشِيٌّ صَبْرًا بَعْدَ هَذَا الْيَوْمِ إِلَى يَوْمِ الْقِيَامَةِ»  

[Machine] I heard the Messenger of Allah ﷺ and he mentioned something similar to it. Abu Muhammad said, "Interpret that as meaning that a Quraishi should not be killed for disbelief, meaning that a Quraishi would not be considered a disbeliever after that day. As for in battle, they should be killed."  

سَمِعْتُ رَسُولَ اللَّهِ ﷺ فَذَكَرَ نَحْوَهُ قَالَ أَبُو مُحَمَّد «فَسَّرُوا ذَلِكَ أَنْ لَا يُقْتَلَ قُرَشِيٌّ عَلَى الْكُفْرِ يَعْنِي لَا يَكُونُ هَذَا أَنْ يَكْفُرَ قُرَشِيٌّ بَعْدَ ذَلِكَ الْيَوْمِ فَأَمَّا فِي الْقَوَدِ فَيُقْتَلُ»