You mean like the NZ Christian who killed Muslims?Does that apply to the Quran?If the Holy Bible would be a forgery God would have already destroyed it
What is Quran?
Who was Muhammad?
To write about is politically incorrect now.Nevertheless I can say following.
Can a 'religion' which kills other believers like in Sri Lanka claim to be from God?
Matthew 7:15
15 Beware of false prophets, which come to you in sheep's clothing, but inwardly they are ravening wolves.