" impartial leader and just judge" and in the tradition narrated by Yunus: the" judge judging with justice" and" impartial leader" are not mentioned. And in the hadith narrated by Salih like the one transmitted by Laith the words are:" impartial judge". And in the hadith transmitted by Ziyad the words are:" Till one sajda is better than the worldand what it contains. Then Abu Huraira used to say," recite" if you like: Not one of the People of the Book will fail to believe in him before his death.  

وَفِي رِوَايَةِ ابْنِ عُيَيْنَةَ إِمَامًا مُقْسِطًا وَحَكَمًا عَدْلاً وَفِي رِوَايَةِ يُونُسَ حَكَمًا عَادِلاً وَلَمْ يَذْكُرْ إِمَامًا مُقْسِطًا وَفِي حَدِيثِ صَالِحٍ حَكَمًا مُقْسِطًا كَمَا قَالَ اللَّيْثُ وَفِي حَدِيثِهِ مِنَ الزِّيَادَةِ وَحَتَّى تَكُونَ السَّجْدَةُ الْوَاحِدَةُ خَيْرًا مِنَ الدُّنْيَا وَمَا فِيهَا ثُمَّ يَقُولُ أَبُو هُرَيْرَةَ اقْرَءُوا إِنْ شِئْتُمْ { وَإِنْ مِنْ أَهْلِ الْكِتَابِ إِلاَّ لَيُؤْمِنَنَّ بِهِ قَبْلَ مَوْتِهِ} الآيَةَ  

"By the One in Whose Hand is my soul! Ibn Mariam shall soon descend among you, judging justly. He shall break the cross, kill the pig, remove the Jizyah, and wealth will be so bountiful that there will be none to accept it."  

أَنَّ رَسُولَ اللَّهِ ﷺ قَالَ وَالَّذِي نَفْسِي بِيَدِهِ لَيُوشِكَنَّ أَنْ يَنْزِلَ فِيكُمُ ابْنُ مَرْيَمَ حَكَمًا مُقْسِطًا فَيَكْسِرَ الصَّلِيبَ وَيَقْتُلَ الْخِنْزِيرَ وَيَضَعَ الْجِزْيَةَ وَيَفِيضَ الْمَالُ حَتَّى لاَ يَقْبَلَهُ أَحَدٌ  

By Him in Whose hand is my life, the son of Mary ﷺ will soon descend among you as a just judge. He will break crosses, kill swine and abolish Jizya and the wealth will pour forth to such an extent that no one will accept it. (Using translation from Muslim 155a)  

قَالَ رَسُولُ اللهِ ﷺ وَالَّذِي نَفْسِي بِيَدِهِ لَيُوشِكُ أَنْ يَنْزِلَ فِيكُمْ ابْنُ مَرْيَمَ حَكَمًا عَادِلًا وَإِمَامًا مُقْسِطًا يَكْسِرُ الصَّلِيبَ وَيَقْتُلُ الْخِنْزِيرَ وَيَضَعُ الْجِزْيَةَ وَيَفِيضُ الْمَالُ حَتَّى لَا يَقْبَلَهَا أَحَدٌ  

Messenger of Allah ﷺ said, "By Him in Whose Hands my soul is, surely (Jesus,) the son of Mary will soon descend amongst you and will judge mankind justly (as a Just Ruler); he will break the Cross and kill the pigs and there will be no Jizya (i.e. taxation taken from non Muslims). Money will be in abundance so that nobody will accept it, and a single prostration to Allah (in prayer) will be better than the whole world and whatever is in it." Abu Huraira added "If you wish, you can recite (this verse of the Holy Book): -- 'And there is none Of the people of the Scriptures (Jews and Christians) But must believe in him (i.e Jesus as an Apostle of Allah and a human being) Before his death. And on the Day of Judgment He will be a witness Against them." (4.159) (See Fath-ul-Bari, Page 302 Vol 7) (Using translation from Bukhārī 3448)   

قَالَ رَسُولُ اللهِ ﷺ وَالَّذِي نَفْسِي بِيَدِهِ لَيُوشِكَنَّ أَنْ يَنْزِلَ فِيكُمُ ابْنُ مَرْيَمَ حَكَمًا عَدْلًا فَيَكْسِرَ الصَّلِيبَ وَيَقْتُلَ الْخِنْزِيرَ وَيَضَعَ الْجِزْيَةَ وَيَفِيضُ الْمَالُ حَتَّى لَا يَقْبَلَهُ أَحَدٌ حَتَّى تَكُونَ السَّجْدَةُ الْوَاحِدَةُ خَيْرًا مِنَ الدُّنْيَا وَمَا فِيهَا ثُمَّ يَقُولُ أَبُو هُرَيْرَةَ اقْرَؤُوا إِنْ شِئْتُمْ {وَإِنْ مِنْ أَهْلِ الْكِتَابِ إِلَّا لَيُؤْمِنَنَّ بِهِ قَبْلَ مَوْتِهِ وَيَوْمَ الْقِيَامَةِ يَكُونُ عَلَيْهِمْ شَهِيدًا} [النساء 159]  

"وَالَّذِي نَفسِي بِيَدهِ لَيُوشِكَنَّ أن ينزلَ ابنُ مريَم فيكُم حَكَمًا مُقْسِطًا، وإمامًا عَدْلًا، فَيَكسِرَ الصليبَ، ويقتلَ الخِنزيرَ ويَضَعَ الجِزْية، ويفيضَ الْمَالُ لا يقبله أحدٌ، وحتى تكونَ السجدةُ الواحدةُ خَيرًا من الدنيا وما فيها".