Tawḥīd — the absolute oneness of Allah
Tawḥīd is not just monotheism in the loose Western sense. It is the assertion that Allah is one in essence, one in worship, and one in attributes — and that any compromise of that oneness is shirk, the only sin Allah specifically says he will not forgive (Q 4:48, Q 4:116). The Qurʼānic statement of pure tawḥīd is Sūrat al-Ikhlās (Q 112) — Say: He is Allah, the One. Allah, the Eternal Refuge. He neither begets nor is begotten, nor is there to him any equivalent. The verse is recited daily by Muslims and is held to express the heart of Islamic theology. The Christian engager should treat tawḥīd seriously, not as a Muslim variation on the Christian one God but as a sharper, more anti-pluralist account that explicitly rules out partners (Trinity, Sonship, intercession by anyone alongside Allah).
The six articles of faith — what every Muslim believes
The classical list comes from the Hadith of Gabriel (Ṣaḥīḥ Muslim 8; Bukhārī 50), where the angel Jibrīl asks Muhammad: what is faith? The answer: belief in (1) Allah, (2) his angels, (3) his books, (4) his messengers, (5) the last day, and (6) divine decree (qadar) — the good and evil of it. The Qurʼān itself summarizes much of this in Q 2:285: The Messenger has believed in what was revealed to him from his Lord, and so have the believers. All of them have believed in Allah and his angels and his books and his messengers. These six articles are not optional or speculative; they define what it means to be a Muslim. A person who denies any of them is, on the classical view, no longer Muslim.
Where this overlaps with Christianity — and where it sharply diverges
Christians and Muslims share a lot here at first glance: one God, real angels, prophetic revelation through history, a final judgment day. The Qurʼān explicitly names many of the same prophets — Adam, Noah, Abraham, Moses, David, Jesus. But the surface overlap hides a structural divergence. Tawḥīd, on classical Sunni reading, is incompatible with the Trinity (which is read as three gods, Q 4:171, Q 5:73) and with the doctrine of the Son of God (which is read as physical begetting, Q 19:35, Q 112:3). The Christian engager should know that an I just believe in one God too response to a Muslim friend is misleading — the kind of one matters. The six articles shape the Muslim heart's expectation of God's character and the rhythm of the world. Honest engagement starts here.
Worked example
The moment
A Muslim friend says, 'We just believe in one God, like Jews. Why do Christians make it complicated?'
What you might say
"That is a fair starting place. Christians do believe in one God — the Bible says so plainly (Deut 6:4). The Trinity is not three gods; it is the one God revealed as Father, Son, and Holy Spirit. Can I tell you what we actually mean? It is not what most Muslims have been told."
Why this works
The answer affirms the friend's monotheistic concern, denies tritheism cleanly, and invites a longer conversation rather than ending in a label.
Watch out for
- Treating tawḥīd as if it were the same word as Christian monotheism — the Muslim concept is sharper and explicitly anti-trinitarian.
- Underestimating the seriousness of shirk in your friend's mind. The fear of associating partners with Allah is one of the deepest religious instincts a Muslim has.
- Listing the six articles in dry summary without recognizing how they shape the moral imagination of the Muslim community.