If you are referring to the Bible (and I know that you are) then it is only because it is a collection of books written by prophets and apostles. Some of the books overlap and some don't. Some use imagery that seems foreign to us but made perfect sense to the people back then. For the most part the Bible is a historical book of God's dealings with the Jews. The New Testaments starts off with 4 books about the History of Jesus. Followed by a book describing what happened to the early Church after Jesus was crucified. Then there are a series of letters written mostly by Paul. Other's written by James and John and then there is the book of Revelation. Revelation is written cryptically on purpose. The people of that time knew what John was saying but the meanings have been lost over time.
The Quran, on the other hand, is not a history book. It is a collection of commandments Allah gave to Mohammad. For whatever reason those commandments were not put in chronological order to when they were given. So it is up to the scholars to figure out which came first and which came last. This is important because where Allah contradicts himself, the later commandment is to be taken as the one to follow. It is basically where Allah changed his mind. He does that a lot in the Quran.
When Mohammad went to Mecca to teach his new religion, they rejected him. Mohammad retreated to the mountains and Allah told him to try to find some compromise between the pagans in Mecca and Allah. So Mohammad tried that approach and they rejected him again. Those verses are now explained away as the "Satanic verses" where Mohammad was supposedly tricked by Satan to make compromises. The next time Mohammad went to Allah, Allah declared jihad on the entire planet. Mohammad was ordered to kill the unbeliever. He was ordered to either kill or tax "the people of the Book" (Christians and Jews). Then later he ordered Mohammad to just kill all of the Jews, every last one of them.
There are a whole lot of strangeness to the Quran and Islam but one of the strange parts is that they believe that Mohammad will return in the last days. And he is going to bring Jesus with him and together they will route out every last Jew and kill them.