MOst people don't understand the historical background of the OT. The Torah , specifically the first four books did exist in oral form except for the ten commandments and the set of laws. No attempt to write the OT existed until the captivity of the Jews in babylon. The fifth book of the Torah follow the language style of Joshua and the books that proceeded them which concludes they were written by the same author/authors.
Anyway, when the Quran mentions the Torah it refers to those set of laws and the tem commandments.
ALl the other books of the OT were never used for worship ceremonies. Not until the Torah was banned they were forced to use the other written material they had to refer to the Torah in a way. After the left of the ban, the jews got into so many debates on whether to include these books or not. They eventually added the books we see today and discarded others.
one interesting story is about the book of Ester. Many Jews objected to the addition of this book because the whole book did not contain the word "GOD". They eventually solved this problem by adding some verses to that book mentioning God in it. This way they have justified the addition. Now the Quran is right when it says that those people added verses and called it the word of God when it is not. However, not until recently those verses from the book of Ester were removed after it was discovered.Many other examples could be illustrated, however, this one simple example is enough for now.
Now when we say the Injil, we do not mean the Gospel that you believe in anyway.To understand our view read the following verses of the Quran:
[3] She said, "My Lord, how can I have a son, when no man has touched me?" He said, "GOD thus creates whatever He wills. To have anything done, He simply says to it, `Be,' and it is.
[3] "He will teach him the scripture, wisdom, the Torah, and the Gospel."
[3] As a messenger to the Children of Israel: "I come to you with a sign from your Lord - I create for you from clay the shape of a bird, then I blow into it, and it becomes a live bird by GOD's leave. I restore vision to the blind, heal the leprous, and I revive the dead by GOD's leave. I can tell you what you eat, and what you store in your homes. This should be a proof for you, if you are believers.
[3] "I confirm previous scripture - the Torah - and I revoke certain prohibitions imposed upon you. I come to you with sufficient proof from your Lord. Therefore, you shall observe GOD, and obey me.
3:51] "GOD is my Lord and your Lord; you shall worship Him alone. This is the right path."
From the above verses the message of Jesus (pbuh) is clear, and the Injil is his message which also include the good new of the upcoming prophet who would be called AHMAD (Muhammad) .
The church ordered all written material about Jesus in Hebrew or Aramaic (jesus's langauge) be destroyed and discarded and only Greece gospels were to be considered. Now one can imagine the problems with tranlations and the many errors that can occur while translating such material. However, more than 22,000 Documents were discarded and the Church in Rome chose those Gospels from those 22,000 documents.
Now, do you want to base on faith on those facts?
Even when they translate the OT to english this is what we encounter:
Gen 3.15
King James Version
And I will put enmity between thee and the woman, and between thy seed and her seed; it shall bruise thy head, and thou shalt bruise his heel.
1917 Jewish Publication Society Bible
And I will put enmity between thee and the woman, and between thy seed and her seed; they shall bruise thy head, and thou shalt bruise their heel.
Ps 2.11-12
King James Version
Serve the LORD with fear, and rejoice with trembling. Kiss the Son, lest he be angry, and ye perish from the way, when his wrath is kindled but a little. Blessed are all they that put their trust in him.
1917 Jewish Publication Society Bible
Serve the LORD with fear, and rejoice with trembling. Do homage in purity, lest He be angry, and ye perish in the way, when suddenly His wrath is kindled. Happy are all they that take refuge in Him.
Ps 22.16
King James Version
For dogs have compassed me: the assembly of the wicked have inclosed me: they pierced my hands and my feet.
1917 Jewish Publication Society Bible
For dogs have encompassed me; a company of evil-doers have inclosed me; like a lion, they are at my hands and my feet.
Isa 53.10-11
Yet it pleased the LORD to bruise him;
1917 Jewish Publication Society Bible
Yet it pleased the LORD to crush him by disease
and many more
The gospels are based on account witnesses in which in each gospel you find a different story. For example. no Gospel agreed on who saw Jesus first after his resurrection, what Jesus said before he died, or to whom did peter deny knowing Jesus.
One simple fact, if those people who thought Jesus was crucified were the account witnesses used in the GOspels we have today, why did you ignore all the other account witnesses which believe that Jesus was not crucified?