Extent of Authority and Knowledge of Imam Hasan (as)
أَحْمَدُ بْنُ مُحَمَّدٍ وَ مُحَمَّدُ بْنُ يَحْيَى عَنْ مُحَمَّدِ بْنِ الْحَسَنِ عَنْ يَعْقُوبَ بْنِ يَزِيدَ عَنِ ابْنِ أَبِي عُمَيْرٍ عَنْ رِجَالِهِ عَنْ أَبِي عَبْدِ اللَّهِ ع قَالَ إِنَّ الْحَسَنَ ع قَالَ إِنَّ لِلَّهِ مَدِينَتَيْنِ إِحْدَاهُمَا بِالْمَشْرِقِ وَ الْأُخْرَى بِالْمَغْرِبِ عَلَيْهِمَا سُورٌ مِنْ حَدِيدٍ وَ عَلَى كُلِّ وَاحِدٍ مِنْهُمَا أَلْفُ أَلْفِ مِصْرَاعٍ وَ فِيهَا سَبْعُونَ أَلْفَ أَلْفِ لُغَةٍ يَتَكَلَّمُ كُلُّ لُغَةٍ بِخِلَافِ لُغَةِ صَاحِبِهَا وَ أَنَا أَعْرِفُ جَمِيعَ اللُّغَاتِ وَ مَا فِيهِمَا وَ مَا بَيْنَهُمَا وَ مَا عَلَيْهِمَا حُجَّةٌ غَيْرِي وَ غَيْرُ الْحُسَيْنِ أَخِي
Ahmad ibn Muhammad and Muhammad ibn Yahya have narrated from Muhammad ibn al-Hassan from Ya‘qub ibn Yazid from ibn abu ‘Umayr from his people from abu ‘Abd Allah (as) who has said the following.
"Al-Hassan (as) has said, ‘Allah has two cities. One is in the east and the other is in the west. They have a boundary around them that is made of iron and each one has a million doors. Seventy thousand different languages exist therein and I know all those languages and all that is therein. There is no one who would possess Leadership with Divine Authority over them except I and my brother al-Husayn (as)."
[Source: Al Kaafi Vol.1 Pg.462]
Note: Authentic Hadees as per the Sanad analysis. See Miraat-Al-Uqool - Allama Majlisi - Vol.5 Pg.357