While working in Bethlehem in the 1980s with Project Redemption, we came to understand Islam as a Christian cult. Mohammad had gotten only a Nestorian view of Christianity. It was an incomplete picture.
Mon. night at a Bible study/study of the Lutheran confessions at Emanuel, we watched a video taped lecture of Tim Wengert, on the confessions. Muslims are mentioned (called Mohammedens) in Article 1 of the Augsburg Confession, along with some other groups. Dr. Wengert explained Islam is considered a christogical heresy. I felt like I was back in Bethlehem! Even Luther and Melancthon viewed Islam as a Christian cult. Though we are divided on the person of Christ, we have numerous commonalities from which to build bridges.
Picture from Photo Galerie German Fulbright.