“Well, it depends on how you define kāfir — in my opinion, a kāfir is someone who… and therefore Christians, Jews, and others are not kāfirs.”

Whenever Muslims hear the violent and inhumane verses of the Quran regarding the slaughter of and brutal treatment of polytheists and unbelievers, they reinvent themselves as the Prophet and fabricate a new intent for God, Qāsim al-Jabbārīn (the Crusher of Tyrants). Your interpretation is respected — but we have no quarrel with the Islam of which you are the prophet. We take issue with the Islam of Muhammad and his Quran, which defines the kāfir as follows.

Chapter One — Identifying the Kāfir, Ahl al-Kitāb, and the Polytheist

1. The lexical meaning of kufr and its applications

2. The nine Quranic meanings of kufr

   1. Denial of the principles of religion
   2. Denial of divine unity (tawḥīd)
   3. Denial of the prophethood of Muhammad
   4. Denial of ṭāghūt (transgressive authority)
   5. Ingratitude for God’s blessings (kufrān al-niʿma)
   6. Abandonment of religious obligations
   7. Commission of sin
   8. Revulsion and disavowal (barāʾa)
   9. Agriculture
3. The five meanings of kufr in hadith literature
4. The five meanings of kufr and kāfir in Shia jurisprudence

Section One: The Meaning of Kufr

§ 1 — Lexical Meaning of Kufr

Although this study focuses specifically on the Ahl al-Kitāb (People of the Book) and polytheists, Shia jurists consistently include them under the category of kāfir — listed among ritual impurities (najāsāt) in their practical treatises. It is therefore essential to clarify the concept from the outset.

According to Arab lexicographers, kufr has one overarching primary meaning: concealment (al-sitr). All secondary meanings are derived from this root concept, including:

1. Kufr as antithesis of faith — concealing and denying truths such as God, the Resurrection, prophethood, and revealed scripture.
2. Ingratitude for blessings — ignoring or misusing God’s gifts; the antithesis of gratitude.
3. The night — which casts a dark veil over all things.
4. Agriculture / the farmer — who conceals seed beneath the soil; hence kāfir = farmer.
5. Donning armour — a soldier who covers his body with a coat of mail.

This analysis is corroborated by the major Arab lexicographers: Rāghib al-Iṣfahānī (al-Mufradāt), Ibn Fāris (Muʿjam Maqāyīs al-Lugha), Ibn Manẓūr (Lisān al-ʿArab), al-Jawharī (Ṣiḥāḥ al-Lugha), al-Zabīdī (Tāj al-ʿArūs), and al-Ṭurayḥī (Majmaʿ al-Baḥrayn).

§ 2 — The Nine Quranic Meanings of Kufr

The word appears more than five hundred times in the Quran in various grammatical forms. Based on its lexical root, it is used in nine distinct senses:

1. Denial of the Principles of Religion

This form of kufr applies to atheists, freethinkers, and materialists who wholesale reject the metaphysical. Example verses:

• “How can you disbelieve in Allāh when you were lifeless and He brought you to life…” (Al-Baqara 2:28)
• “And what prevents their expenditures from being accepted from them but that they have disbelieved in Allāh…” (Al-Tawba 9:54)
• “Indeed, those who disbelieve in Allāh and His messengers…” (Al-Nisāʾ 4:150)
• “Those are the ones who disbelieve in the verses of their Lord and in [their] meeting Him…” (Al-Kahf 18:105)
• “…whoever disbelieves in Allāh, His angels, His books, His messengers, and the Last Day has certainly gone far astray.” (Al-Nisāʾ 4:136)

2. Denial of Divine Unity (Tawḥīd)

In this sense kufr equals shirk (polytheism) and includes dualists, trinitarians, idol-worshippers, and polytheistic factions within the People of the Book.

• “They have certainly disbelieved who say, ‘Allāh is the third of three.’…” (Al-Māʾida 5:73)
• “They have certainly disbelieved who say ‘God is the Messiah, son of Mary’…” (Al-Māʾida 5:17, 72)

3. Denial of the Prophethood of Muhammad

This encompasses all non-Muslims — including followers of other revealed religions.

• “And those who have disbelieved say, ‘You are not a messenger.’…” (Al-Raʿd 13:43)
• “Neither those who disbelieve from the People of the Scripture [i.e., the Jews and Christians] nor the polytheists wish that any good should be sent down to you from your Lord…” (Al-Baqara 2:105)

4. Denial of Ṭāghūt (transgressive authority)

This is a praiseworthy form of kufr — rejecting false gods and tyrannical powers is a prerequisite of true faith.

• “Whoever disbelieves in ṭāghūt and believes in God has grasped the most trustworthy handhold…” (Al-Baqara 2:256)

5. Ingratitude for Blessings (Kufrān al-Niʿma)

The antithesis of gratitude — squandering God’s gifts or using them in ways contrary to His will.

• “…’If you are grateful, I will surely increase you [in favor]; but if you deny, indeed, My punishment is severe.'” (Ibrāhīm 14:7)
• “…This is from the favor of my Lord to test me whether I will be grateful or ungrateful…” (Al-Naml 27:40)
• “So remember Me; I will remember you. And be grateful to Me and do not deny Me.” (Al-Baqara 2:152)
• “…So Allāh made it taste the envelopment of hunger…” (Al-Naḥl 16:112)

6. Abandonment of Religious Obligations

The Quran designates the wilful abandonment of obligations such as the ḥajj as a form of kufr.

• “…And [due] to Allāh from the people is a pilgrimage to the House – for whoever is able to find thereto a way. But whoever disbelieves [i.e., refuses] – then indeed, Allāh is free from need of the worlds.” (Āl ʿImrān 3:97)

7. Commission of Sin

In several instances the Quran labels prohibited acts — such as sorcery or crimes against innocent people — as kufr.

• “…they followed [instead] what the devils had recited during the reign of Solomon. It was not Solomon who disbelieved, but the devils disbelieved, teaching people magic…” (Al-Baqara 2:102)
• “…So do you believe in part of the Scripture and disbelieve in part?…” (Al-Baqara 2:85)

8. Revulsion and Disavowal (Barāʾa)

• “…Then on the Day of Resurrection you will deny one another and curse one another, and your refuge will be the Fire…” (Al-ʿAnkabūt 29:25)
• “…We have denied you, and there has appeared between us and you animosity and hatred forever until you believe in Allāh alone…” (Al-Mumtaḥana 60:4)
• “Satan said [on the Day of Judgement]: …’Indeed, I deny your association of me [with Allāh] before.’…” (Ibrāhīm 14:22)

9. Agriculture

In a single instance the Quran uses kufr in its original sense of “burying seed in the ground,” applying the term kuffār to farmers:

• “Know that the life of this world is but amusement and diversion… like rain whose resulting plant growth pleases the kuffār (farmers), then it withers and you see it turned yellow…” (Al-Ḥadīd 57:20)

In the Light of the Infallible Imam

Imam Jaʿfar al-Ṣādiq was asked by Zubayrī to explain the meanings of kufr in the Quran. The Imam’s response — recorded in Uṣūl al-Kāfī (Vol. 2, Bāb Wujūh al-Kufr, p. 389) — distils these meanings into five categories:

1. Kufr of denial (juḥūd) — outright rejection of God’s lordship; the creed of those who say there is no God, no paradise, no hellfire.
2. Conscious denial — rejecting that which one already knows to be true, out of wrongdoing and arrogance: “And they rejected them, while their [inner] selves were convinced thereof, out of injustice and haughtiness” (Q. 27:14).
3. Ingratitude for blessings — misusing God’s gifts and failing to give thanks, as illustrated by Solomon’s words in Q. 27:40.
4. Abandoning divine commandments — failing to fulfil obligations God has prescribed, as in Q. 2:85.
5. Revulsion and disavowal (barāʾa) — renouncing others, as Abraham renounced his polytheist community (Q. 60:4).

The Imam concludes with a critical methodological caution: the legal rulings (aḥkām) specific to each category of kufr must not be applied to individuals who fall only under a different category. For example, Jews and Christians are kāfir in the third sense (denial of Muhammad’s prophethood) but not in the first sense (denial of God).

§ 3 — The Five Meanings of Kufr in Hadith Literature

The usage of kufr in hadith hardly differs from its usage in the Quran. Across more than five thousand instances in Biḥār al-Anwār, five categories emerge:

1. Denial of God’s Unity or Attributes

Encompasses all atheists, materialists, polytheists, and agnostics.

• “Whoever asserts anthropomorphism or absolute determinism is a kāfir.” — Biḥār al-Anwār, vol. 5, p. 35
• “Doubt is itself kufr.” — vol. 21, p. 211

2. Denial of Prophethood (General or Specific)

Includes all those who reject the revealed scriptures, and also those who reject the Quran, such as Jews and Christians.

• “Whoever rejects the Book of God is a kāfir.” — vol. 25, p. 121
• “Who are the unbelievers?” — “Those who disbelieve in my grandfather, the Messenger of God.” — vol. 47, p. 358

3. Denial of the Resurrection or Its Details

Some traditions count deniers of transmigration of souls (tanāsukh) among unbelievers.

• “Whoever believes in the transmigration of souls is a kāfir.” — vol. 4, p. 320

4. Denial of the Imamate

Some of the traditions concern deniers of the Imamate of ʿAlī ibn Abī Ṭālib or of all the infallible Imams. These traditions count any deviation from the path of the Imamate of the Twelve Imams as kufr, for example: disputing with ʿAlī over the caliphate, hostility toward him, rejecting his rule and authority (wilāya), failing to recognise the Imam of the Age, and doubting the Imamate of ʿAlī.

5. Commission of Sin

The majority of hadith employing the term relate to specific transgressions, including:

• “Whoever dares to commit grave sins is a kāfir.” — vol. 72, p. 222
• “The abandonment of prayer is what separates the Muslim from the kāfir.” — vol. 35, p. 155
• “One who abandons taqiyya is a kāfir.” — vol. 78, p. 347
• “One who can afford ḥajj and neglects it is a kāfir.” — vol. 77, p. 58
• “The drinker of wine is a kāfir.” — vol. 79, p. 141
• “The sorcerer is a kāfir.” — vol. 79, p. 212
• “Indeed, ingratitude for a blessing from the mother is kufr.” — vol. 77, p. 213
• “Whoever calls his [Muslim] brother an unbeliever — one of the two has thereby committed kufr.” — vol. 10, p. 102
• “Whoever befriends a kāfir becomes a kāfir.” — vol. 74, p. 197

§ 4 — The Five Categories of Kāfir in Shia Jurisprudence

Following the Quran and hadith, Shia jurists apply the term kāfir to five groups (with some scholarly disagreement):

1. Deniers of God, or materialists
2. Polytheists
3. Followers of other revealed religions — Jews, Christians, and Zoroastrians (the People of the Book)
4. Those who knowingly deny an established necessity of religion — including Khārijites, Nāṣibīs, and certain extremist sects (ghulāt)
5. Deniers of the Imamate

Shia jurists are unanimous regarding the first three groups. On the fourth, opinion is divided: some scholars consider all sub-categories both unbelievers and ritually impure; others accept their ritual impurity while declining to declare them unbelievers outright; a minority disputes even their impurity. Regarding the fifth group, while most Shia jurists do not label deniers of the Imamate as kāfir, a small number count them as kāfir in the sense of denying the truth of the Imamate. In practice, the term kāfir in Shia jurisprudence is effectively confined to the first four categories.

Conclusion: Accordingly, according to these Islamic scholars, a kāfir is anyone who is not a Muslim! Please do not try to give Islam a metallic paint job and put lipstick on it! The savage nature of Islam cannot be changed.

References

1. Rāghib al-Iṣfahānī, al-Mufradāt fī Gharīb al-Qurʾān, p. 433
2. Ibn Fāris, Muʿjam Maqāyīs al-Lugha, vol. 5, p. 91
3. Ibn Manẓūr, Lisān al-ʿArab, vol. 5, p. 144
4. Al-Jawharī, Ṣiḥāḥ al-Lugha, vol. 2, p. 807
5. Al-Zabīdī, Tāj al-ʿArūs, vol. 3, p. 535
6. Al-Ṭurayḥī, Majmaʿ al-Baḥrayn, vol. 3, p. 474
7. Uṣūl al-Kāfī, vol. 2, Bāb Wujūh al-Kufr, p. 389
8. Biḥār al-Anwār (various volumes — see footnotes 29–47 in original)