About Iman (faith) in Islam

About Iman
Some definitions about Iman (faith):

Anas related that Prophet Muhammad ﷺ (peace be upon him) seldomly addressed us without saying:

          "He who is not trustworthy has no faith and he who does not keep his promise has no 
          religion." (Baihaqi)


Abu Umamah reported that a man once asked Prophet Muhammad ﷺ (peace be upon him), 'What is faith?' He replied:

          "When your good deeds make you happy and your bad deeds make you 

          sad, you have faith."

And then the man asked him, 'What is sin?' And Prophet Muhammad ﷺ (peace be upon him) replied:

          "When anything pricks your conscience, avoid it." (Ahmed)