Wabisah bin Ma’bad (r.a.) reported: I went to the Messenger of Allah and he asked me “ Have you come to inquire about piety?” I (Wabisah bin Ma’bad (r.a.) )replied in the affirmative.
Then he (Prophet Muhammad (peace be upon him) said, “ Ask your heart regarding it. Piety is that which contents the soul and comforts the heart and sin is that which causes doubts and perturbs (to disturb greatly) the heart, even if people pronounce it lawful and gives you verdicts on such matters again and again.”
Hadith No. 591 Ahmad and Ad -Darmi
Commentary: Man’s heart is the biggest guide to him and he therefore, should keep his heart illuminated with the light of faith so as to continue receiving guidance from it.