Hadith

 حَدَّثَنَا مُحَمَّدُ بْنُ عَلِيٍّ مَاجِيلَوَيْهِ رَحِمَهُ اَللَّهُ عَنْ أَبِي عَبْدِ اَللَّهِ ع قَالَ : قَالَ لَهُ أَبُو جَعْفَرٍ اَلدَّوَانِيقِيُّ بِالْحِيرَةِ أَيَّامَ أَبِي اَلْعَبَّاسِ يَا أَبَا عَبْدِ اَللَّهِ مَا بَالُ اَلرَّجُلِ مِنْ شِيعَتِكُمْ يَسْتَخْرِجُ مَا فِي جَوْفِهِ فِي مَجْلِسٍ وَاحِدٍ حَتَّى يُعْرَفَ مَذْهَبُهُ فَقَالَ ع ذَلِكَ بِحَلاَوَةِ اَلْإِيمَانِ فِي صُدُورِهِمْ مِنْ حَلاَوَتِهِ يُبْدُونَهُ تَبَدِّياً .

 Mohammad bin Ali Majilwayh, Allah may have mercy upon him, … In al-Hira during the reign of Abu al-Abbas, Abu Ja’far ad-Dawaniqi said to Imam Abu Abdullah (a) “O Abu Abdullah, I noticed that any individual of the Shia speak out all that he hides in one session so that his trend would be easily known. Why is that?” The Imam (a) answered: This is because of the sweetness of faith that the Shia carry in their chests. For that sweetness, they show the hidden all at once.

Ṣifāt al-Shīʿa

Book 1, Chapter 27