كَتَبْتُ مَعَ عَبْدِ الْمَلِكِ بْنِ أَعْيَنَ إِلَى أَبِي عَبْدِ اللَّهِ ع أَسْأَلُهُ عَنِ الْإِيمَانِ مَا هُوَ فَكَتَبَ إِلَيَّ مَعَ عَبْدِ الْمَلِكِ بْنِ أَعْيَنَ سَأَلْتَ رَحِمَكَ اللَّهُ عَنِ الْإِيمَانِ وَ الْإِيمَانُ هُوَ الْإِقْرَارُ بِاللِّسَانِ وَ عَقْدٌ فِي الْقَلْبِ وَ عَمَلٌ بِالْأَرْكَانِ وَ الْإِيمَانُ بَعْضُهُ مِنْ بَعْضٍ وَ هُوَ دَارٌ وَ كَذَلِكَ الْإِسْلَامُ دَارٌ وَ الْكُفْرُ دَارٌ فَقَدْ يَكُونُ الْ
“Abd al-Malik ibn A’yan and I wrote to Abu ‘Abdillah (a.s.) asking him, ‘What is belief?’ He then wrote to us. ‘You, may Allah grant you favors, have asked about belief. Belief is affirmation, with the tongue, that is established in the heart and by the deeds of the body. Beliefs are from each other. Belief is a house.