The essence of belief in heart, tongue, and action
Nahj al-Balāgha|Volume 1|Book 3|Chapter 227
٢٢٧. وَسُئِلَ عَنِ الْإِيمَانِ فَقَالَ الْإِيمَانُ مَعْرِفَةٌ بِالْقَلْبِ، وَإِقْرَارٌ بِاللِّسَانِ، وَعَمَلٌ بِالْأَرْكَانِ.
227. Amīr al-mu’minīn, peace be upon him, was asked about belief (īmān) when he said: Belief means appreciation with the heart, acknowledgement with the tongue, and action with the limbs.