Despite what Islam says (which arrived on the scene at least 600 years after the advent of Christianity) the Christian religion is not derived from nor even based on Scriptures. It antecedes the New Testament. It is not a "religion of the book" like Islam. Never has been. The New Testament did not exist for decades after Christ's resurrection, yet the people were Christians and preached everywhere that Jesus was God incarnate, died and was resurrected and ascended into heaven. The New Testament in its current canon was not finalised until centuries after the resurrection of Christ. No early Christian evangelist and preacher for centuries went round carrying a New Testament - it didn't exist.
No, Christ founded a Church, with a real and living authority that teaches and preaches with the same authority as he did, ie with divine authority. The bible is NOT the pillar and foundation of truth for Christians (though it is for maybe 30% who call themselves Protestants, but they ignore what even the Bible itself says on this very point). If every Bible in earth vanished, the truth would still be preached and lived. I know it's useless citing biblical passages for these points (which I can; they exist in the New Testament), because there's little point in quoting a scripture when the veracity or authenticity of that scripture is itself under question.
Rather, Christianity is founded by and on a Person, who is the Incarnate Word of God. That person is known in history as Yeshua, or Jesus of Nazareth. His own mission he handed on to his Apostles (who are not the same as ordinary disciples - apostolos means "sent one") - he gave the Apostles the same authority he has, including the power to forgive sins in his name, which is a power only God has. The Apostles understood that they had a unique mission and position in the Church, that is why they elected a successor to Judas after his suicide. The position is called "overseer" or "supervisor" in the New Testament, using the Greek word episkopos, which comes down to English as Bishop. If a 'church' does not have a Bishop who is in communion with the other Bishops of the Universal (kataholos, or catholic) Church, then that 'church' is a man-made creation and not the one established by Christ. There are today over 35,000 'christian' sects, each claiming to interpret the Bible authentically. And each and every one of them is premised on the same mistaken notion that the Bible is the sole rule of faith. It is not.
Pls read your post again then watch this video its an hour long and a bit.
Every teaching of Islam is a manifestation of Divine mercy, and any understanding of Islam that lacks mercy, lacks understanding,