Depending on the religion, faith is belief in a god or gods or in the doctrines or teachings of the religion. Informal usage of faith can be quite broad, including trust or belief without proof, and “faith” is often used as a substitute for “hope”, “trust” or “belief”. Some[who?] critics of faith have argued that faith is opposed to reason. In contrast, some[who?] advocates of faith argue that the proper domain of faith concerns questions which cannot be settled by evidence. This is exemplified by attitudes about the future, which (by definition) has not yet occurred.
In Islam, faith (iman) is complete submission to the will of God, which includes belief, profession and the body’s performance of deeds, consistent with the commission as vicegerent on Earth, all according to God’s will.
Iman has two aspects:
Recognizing and affirming that there is one Creator of the universe and only to this Creator is worship due. According to Islamic thought, this comes naturally because faith is an instinct of the human soul. This instinct is then trained via parents or guardians into specific religious or spiritual paths. Likewise, the instinct may not be guided at all.
Willingness and commitment to submitting that God exists, and to His prescriptions for living in accordance with vicegerency. The Qur’an is understood as the dictation of God’s prescriptions through the Prophet Muhammad and is believed to have updated and completed the previous revelations that God sent through earlier prophets.
In the Qur’an, it is stated that (2:62): “Surely, those who believe, those who are Muslims, Jewish, the Christians, and the Sabians; anyone who (1) believes in GOD, and (2) believes in the Last Day, and (3) leads a righteous life, will receive their recompense from their Lord. They have nothing to fear, nor will they grieve.