The Prophet ﷺ went out on a cold morning while the Muhajirin (emigrants) and the Ansar were digging the trench. The Prophet ﷺ then said, "O Allah! The real goodness is the goodness of the Here after, so please forgive the Ansar and the Muhajirin." They replied, "We are those who have given the Pledge of allegiance to Muhammad for to observe Jihad as long as we remain alive." (Using translation from Bukhārī 7201)   

خَرَجَ النَّبِيُّ ﷺ فِي غَدَاةٍ بَارِدَةٍ وَالْمُهَاجِرُونَ وَالْأَنْصَارُ يَعْنِي يَحْفِرُونَ الْخَنْدَقَ فَقَالَ «اللهُمَّ إِنَّ الْخَيْرَ خَيْرُ الْآخِرَهْ فَاغْفِرْ لِلْأَنْصَارِ وَالْمُهَاجِرَهْ» فَأَجَابُوهُ [البحر الرجز] نَحْنُ الَّذِينَ بَايَعُوا مُحَمَّدَا عَلَى الْجِهَادِ مَا بَقِينَا أَبَدَا  

When the Prophet ﷺ called the people (Sadqa, a sub-narrator, said, 'Most likely that happened on the day of Al-Khandaq) Az-Zubair responded to the call (i.e. to act as a scout). The Prophet) called the people again and Az-Zubair responded to the call. The Prophet ﷺ then said, "Every prophet had a disciple and my disciple is Zubair bin Al-ʿAwwam." (Using translation from Bukhārī 2847)   

سَمِعْتُ جَابِرَ بْنَ عَبْدِ اللهِ يَقُولُ نَدَبَ رَسُولُ اللهِ ﷺ يَوْمَ الْخَنْدَقِ فَانْتُدِبَ الزُّبَيْرُ ثُمَّ نَدَبَهُمْ فَانْتُدِبَ الزُّبَيْرُ ثُمَّ نَدَبَهُمْ فَانْتُدِبَ الزُّبَيْرُ فَقَالَ «إِنَّ لِكُلِّ نَبِيٍّ حَوَارِيًّا وَحَوَارِيَّ الزُّبَيْرُ»