al-Īmān is interpreted in four senses:
1. al-īmān is used in the sense of verbal acknowledgment of iman (faith) by the tongue without affirmation (taṣdīq) in the heart; this is the case in the following verses:
That is: they have believed {that is, they have openly acknowledged with their tongues}, then they disbelieved {that is, they secretly disbelieved; they did not affirm the Prophet (peace and blessings be upon him) and what he brought}, so their hearts were sealed, and they do not understand. (al-Munāfiqūn 63:3)
O you who have believed {that is, those who have acknowledged with their tongues without affirmation in their (hearts)}! Let not your wealth and your children divert you from the remembrance of Allah. (al-Munāfiqūn 63:9)
Has the time not come for those who have believed {that is, those who have acknowledged with their tongues without affirmation in their hearts} for their hearts to become humbly submissive to the remembrance of Allah? (al-Ḥadīd 57:16)
O you who have believed {that is, those who have acknowledged (with their tongues) without affirmation in their hearts}! Do not take as allies a people with whom Allah is angry! (al-Mumtaḥina 60:13)
2. The term al-īmān is used in the sense of affirmation (taṣdīq) both inwardly and outwardly; as in the following verses:
Indeed, those who have believed (that is, those who affirm both outwardly and inwardly) and done righteous deeds—those are the best of creatures. (al-Bayyina 98:7)
To admit the believing men and believing women {that is, the believing men and women who affirm both outwardly and inwardly} to gardens beneath which rivers flow... (al-Fatḥ 48:5)
There are many similar statements.
3. al-īmān is used in the sense of tawhid (the oneness of God); as in the following verses:
Whoever disbelieves in iman {that is, in tawhid}—his deeds have become worthless. (al-Māʾida 5:5)
You were being called to iman {that is, to tawhid}, but you disbelieved. (al-Muʾmin 40:10)
Except for those who were compelled while their hearts were at rest with iman {that is, with tawhid}... (al-Naḥl 16:106)
4. By al-īmān, iman (faith) accompanied by shirk (associating partners with God) is intended; as in the following verse:
Most of them do not believe in Allah except while they associate others with Him. (Yūsuf 12:106)
In this verse, the faith of the Arab polytheists and their manner of believing is discussed.
And if you asked them, "Who created them?" they would surely say, "Allah." (al-Zukhruf 43:87)
And if you asked them, "Who created the heavens and the earth?" they would surely say, "Allah." (Luqmān 31:25 and al-Zumar 39:38)
Such is their iman; yet, in this state, they commit shirk with Allah. The People of the Book also believe in some of the messengers and scriptures, but deny others. About such people, Allah says: "It is those who are the disbelievers, truly." (al-Nisāʾ 4:151) Therefore, their belief in some of the messengers and scriptures does not benefit them, because they have not believed in all of them.