In a discussion with a Muslim, he asked:
We believe that Jesus is in heaven, that he is one of the most beloved prophets, al-Masih, and we highly respect him. Why wouldn't that suffice?
Islam says that on the day of judgment, our good deeds will be weighed against our bad deeds on the scales of justice. (
Al-'Anbyā' 21:47) That's bad news, since as the prophet Isaiah tells us, even our "righteous acts are like filthy rags." (
Isaiah 64:6) Nothing we've done is untainted by sin and selfishness.
On the other hand, we're offered forgiveness via the perfect sacrifice of Jesus. Forgiveness! Absolution! Mercy! That's good news. We no longer have to climb an infinite ladder to God. Jesus himself is the ladder, and he himself has come down from heaven for us and for our salvation, and he has returned to heaven, making a way for us. None of that is possible without him being "true God in order to conquer death by his power, and truly human that he might die for us in the weakness of his flesh." (
Belgic Confession,
Art. 19)
Implicitly, this Muslim is asking what one must confess to be saved. Of course, the Muslim answer is, "There is no god but Allah, and Muhammad is his messenger." But Christians have always had a different answer: "If you confess with your mouth that Jesus is Lord and believe in your heart that God raised him from the dead, you will be saved." (
Romans 10:9)
And returning for a moment to the idea of the scales of justice, that too was repudiated in the earliest days of Christianity: "A person is not justified by the works of the law, but by faith in Jesus Christ. … I do not set aside the grace of God, for if righteousness could be gained through the law, Christ died for nothing!" (
Galatians 2:16,21)
That's entirely contrary to Islam's view of judgment, and it's completely based on Christ's death and resurrection (which Jesus predicted many times, unambiguously, throughout his ministry). Christians have always viewed Christ's death and resurrection as essential tenets of faith. If that aspect of the Bible was corrupted, it might be worth asking why God allowed his servant's words and actions to be so
hopelessly manipulated so
incredibly early.