According to the authentic Hadīth of ʿUmar bin al-Khattāb (May Allāh be pleased with him), Imām Muslim and others reported that the angel Jibrīl appeared before the Prophet (May Allāh elevate his rank & grant him peace) in the form of a man. Jibrīl asked the Prophet (May Allāh elevate his rank & grant him peace) about various aspects of faith, starting with Islām, then ʾĪmān, and finally ʾIḥsān.

When asked about (faith), the Prophet (May Allah increase his position and grant him peace) delivered a detailed response, outlining six key characteristics that compose the core of faith:

Have faith in Allah.
Have faith in His Angels.
Have Faith in His Books.
Have faith in His Messengers.
Belief in the Second Coming.
Belief in Divine Decree and Ordainment,

which includes both the good and the terrible. Imām Muslim and others authentically reported in the Hadīth of ʿUmar bin al-Khattāb (May Allāh be pleased with him) that the angel Jibrīl came to the Prophet (May Allāh elevate his rank & grant him peace) in the image of a man asking him about Islām, ʾĪmān, ʾIḥsān, and finally asked him about the signs of the Last Hour. So, the Prophet (May Allāh elevate his rank & grant him peace) when asked about ʾĪmān he answered by saying:“ʾĪmān is that you believe in Allāh, His Angels, His Books, His Messengers, the Last Day, and that you believe in the Divine Decree and Ordainment; the good of it as well as the bad.”Our Noble Prophet (May Allāh elevate his rank & grant him peace) clarified in this tremendous Ḥadīth the fundamentals of our belief and creed, distinguishing the believer from the disbeliever.