It is narrated from Sayyiduna Umar (may Allah be pleased with him) that Jibreel (peace be upon him) once asked the Prophet (peace and blessings be upon him), "What is faith?" He replied: "Faith is that you believe in Allah, His angels, His books, His messengers, the Last Day, and in destiny, its good and its bad." Jibreel (peace be upon him) said: "You have spoken the truth." We were amazed that he was asking questions and also confirming the answers. Later, the Prophet (peace and blessings be upon him) informed us that this was Jibreel who came to teach you the important matters of your religion.