Can a person who believes that Jesus is the son of God be a Muslim?

One of the most important principles of belief in Allaah is
to declare that Allaah is above all attributes that imply shortcomings. One
of the attributes that imply shortcomings that the Muslim must reject is the
notion that Allaah has a son, because that implies need and that there is a
being who is like unto Him, and these are matters which Allaah is far above.
Allaah says in Soorat al-Ikhlaas, which describes an attribute of the Most
Merciful and is regarded as being equal in reward to reciting one-third of
the Qur’aan: 

“Say (O Muhammad): He is Allaah, (the) One.

Allaah-us-Samad [Allaah — the Self-Sufficient Master, Whom
all creatures need, (He neither eats nor drinks)].

He begets not, nor was He begotten.

And there is none co-equal or comparable unto Him”

[al-Ikhlaas 112:1-4 – interpretation of the meaning]

Because the Christians believe that ‘Eesa (Jesus) is the son
of God – exalted be Allaah far above what they say – many verses of the
Qur’aan deny this claim and refute it, as Allaah says (interpretation of the
meaning): 

“And the Jews say: ‘Uzair
(Ezra) is the son of Allaah, and the Christians say: Messiah is the son of
Allaah. That is their saying with their mouths, resembling the saying of
those who disbelieved aforetime. Allaah’s Curse be on them, how they are
deluded away from the truth!”

[al-Tawbah 9:30]

“O people of the Scripture (Christians)! Do not exceed the
limits in your religion, nor say of Allaah aught but the truth. The Messiah
‘Eesa (Jesus), son of Maryam (Mary), was (no more than) a Messenger of
Allaah and His Word, (‘Be!’ — and he was) which He bestowed on Maryam (Mary)
and a spirit (Rooh) created by Him; so believe in Allaah and His Messengers.
Say not: ‘Three (trinity)!’ Cease! (it is) better for you. For Allaah is
(the only) One Ilaah (God), glory is to Him (Far Exalted is He) above having
a son. To Him belongs all that is in the heavens and all that is in the
earth. And Allaah is All-Sufficient as a Disposer of affairs”

[al-Nisa’ 4:171]

“The Messiah [‘Eesa
(Jesus)], son of Maryam (Mary), was no more than a Messenger; many were the
Messengers that passed away before him. His mother [Maryam (Mary)] was a
Siddeeqah [i.e. she believed in the Words of Allaah and His Books]. They
both used to eat food (as any other human being, while Allaah does not eat).
Look how We make the Ayaat (proofs, evidences, verses, lessons, signs,
revelations, etc.) clear to them; yet look how they are deluded away (from
the truth)”

[al-Maa’idah 5:75]

 “And the Jews say: ‘Uzair (Ezra) is the son of Allaah, and
the Christians say: Messiah is the son of Allaah. That is their saying with
their mouths, resembling the saying of those who disbelieved aforetime.
Allaah’s Curse be on them, how they are deluded away from the truth!”

[al-Tawbah 9:30]

Because this false belief existed among the Christians, it
was essential for those among them who entered Islam to give up these false
beliefs which contradict Islam, one of which is this belief. It was narrated
that the Prophet (peace and blessings of Allaah be upon him) said:
“Whoever bears witness that there is no god except Allaah alone, with no
partner or associate, and that Muhammad is His slave and Messenger and that
‘Eesa is His slave and Messenger, and His Word which He bestowed upon Maryam
and a spirit created by Him, and that Paradise is real and Hell is real,
Allaah will admit him to Paradise (and grant him a position therein)
according to his deeds.” (al-Bukhaari, 3435; Muslim, 28). Al-Qurtubi (may
Allaah have mercy on him) said: From this it may be understood what the
Christian must be taught to say when he becomes a Muslim. Fath al-Baari,
hadeeth no. 3435.

 Based on this, a person can only be regarded as a Muslim if
he disavows himself of this false belief, and believes that Allaah is above
all shortcomings. Whoever acknowledges the greatness of Allaah will find it
easy to give up his old beliefs that are not appropriate with regard to
Allaah. We ask Allaah to help us to venerate Him and appreciate how great He
is.