يَـٰٓأَهْلَ ٱلْكِتَـٰبِ لَا تَغْلُوا۟ فِى دِينِكُمْ وَلَا تَقُولُوا۟ عَلَى ٱللَّهِ إِلَّا ٱلْحَقَّ ۚ إِنَّمَا ٱلْمَسِيحُ عِيسَى ٱبْنُ مَرْيَمَ رَسُولُ ٱللَّهِ وَكَلِمَتُهُۥٓ أَلْقَىٰهَآ إِلَىٰ مَرْيَمَ وَرُوحٌ مِّنْهُ ۖ فَـَٔامِنُوا۟ بِٱللَّهِ وَرُسُلِهِۦ ۖ وَلَا تَقُولُوا۟ ثَلَـٰثَةٌ ۚ ٱنتَهُوا۟ خَيْرًا لَّكُمْ ۚ إِنَّمَا ٱللَّهُ إِلَـٰهٌ وَٰحِدٌ ۖ سُبْحَـٰنَهُۥٓ أَن يَكُونَ لَهُۥ وَلَدٌ ۘ لَّهُۥ مَا فِى ٱلسَّمَـٰوَٰتِ وَمَا فِى ٱلْأَرْضِ ۗ وَكَفَىٰ بِٱللَّهِ وَكِيلًا
Qur’an 4:171
This ayat describes Isa as ‘كَلِمَتُهُۥٓ’ (his word) and ‘وَرُوحٌ مِّنْهُ ۖ’ (a spirit of him).
Reading a book recently about John of Damascus*, I was struck by a question that John alluded to in ‘Heresy of the Ishmaelites’, where he argued against the developing Islamic influence around him in Damascus in the early 8th century.
Taking as our starting point the doctrine of Tawhid, and the isolated oneness of Allah, by which I mean the belief that Allah is a monad, and wholly separate from creation. Then we recognise that, to Muslims, Isa is just a man. On no account is he divine, but I want to suggest to you, that when we come to Surah 4:171, you are left with big, big problems.
1) As Allah is wholly separate, how can he share his word and his spirit with a man? He can’t, otherwise Muslims will become associators.
2) As he cannot share his word with a man, he must then give his word to Isa. But if Allah gives his word to the man Isa, then Allah has no word. Allah has been struck dumb.
3) As he cannot share his spirit with a man, he then must give his spirit to Isa. Again, like in point 2, this leaves Allah with no spirit. Allah is dead and Isa becomes Allah.
‘Allah is Dead and Isa becomes Allah’
The problem for Islam is that so much has been borrowed from Christianity, especially from the Arian heresy, and as the collators of the Qur’an sought to mix this with their own anti-Byzantine Roman rhetoric they ended up with these monumental contradictions.
The Trinity is the Solution
In the Bible, Jesus is also referred to as the Word of God (John 1:1), who is indwelt by the Spirit of God (Luke 4:1). However, because the Bible, from start to end, declares God to be Triune, Christians do not have the same problem.
You’ve likely read this before, but let’s consider how John’s Gospel commences once more:
‘In the beginning was the Word, and the Word was with God, and the Word was God.’
John 1:1
Because Father, Son and Holy Spirit are One God, they share essential deity. Because they are One, there is no problem with the Son coming into our world as the Word of God to reveal the Father to us. And because God, while He remains utterly holy, is not wholly separate from His creation, the eternal Son, the Word of God, can come down, and humble Himself to become a man indwelt by the Spirit of God, to become ‘God our Saviour’, Jesus Christ.
So now, we can say that Jesus is God, He died for our sins, but on the third day, rose again in the power of an endless life.
Hallelujah!
* John of Damascus – First Apologist to the Muslims, Daniel J. Janosik (2016)
Forward in Hope 
Your reasoning is very weird, like proving something by first stating that a must be be so b is a.
Nowhere in Scripture is said that God exist out of three different personalities. The opposite is said in the Bible, where clearly is written that God is One Eternal Being that always stays the same and Who can not be seen by man. Jesus was not eternal, did not know everything, could and did die. He clearly did know his position and was declared by God to be His only begotten beloved son. Do you not believe those words of God then?
It doesn’t sound like you’re actually engaging with what I wrote. It was only in the first half of this post (dealing with the Qur’an) that I was reasoning, and in that I was showing the contradiction, which could be put as the Qur’an saying 1) A is not B, and 2) A is B.
However, it sounds more like you were referring to the second half of my post where I address the Deity of Christ. In this section, I was not reasoning. I was simply stating the facts clearly declared in Scripture of a Triune God, and that Jesus Christ is the eternal and co-equal Son. If you are patient I plan to show the truth of this in coming posts.
For now, here’s a verse of Scripture for you to meditate on: ‘And without controversy great is the mystery of godliness: God was manifest in the flesh, justified in the Spirit, seen of angels, preached unto the Gentiles, believed on in the world, received up into glory.’ [1 Tim 3:16] … and a question: how do you explain that ‘no man hath seen God at any time’ (John 1:18) and ‘God was manifest in flesh’?
Jesus like other prophets came to declare God and by the Word of God people could come to know God. He is still manifest in His Word which is available to the whole world.