عَنْ زَيْدِ بْنِ خَالِدٍ الْجُهَنِيِّ رَضِيَ اللَّهُ عَنْهُ أَنَّ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ قَالَ أَلَا أُخْبِرُكُمْ بِخَيْرِ الشُّهَدَاءِ الَّذِي يَأْتِي بِشَهَادَتِهِ قَبْلَ أَنْ يُسْأَلَهَا أَوْ يُخْبِرُ بِشَهَادَتِهِ قَبْلَ أَنْ يُسْأَلَهَا
Narrated by Sayyiduna Zaid bin Khalid Al-Juhani (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: Shall I not tell you who is the best witness? He is the one who gives testimony before he is asked for it.