Editing Sect of Muḥammad

For many centuries Christians referred to Islam as a Christian heresy. The first Christian referred to Islam in this way was [https://en.wikipedia.org/wiki/John_of_Damascus John of Damascus].Then also [https://en.wikipedia.org/wiki/Peter_the_Venerable Peter the Venerable], who gave an important contribution to the [https://en.wikipedia.org/wiki/Christianity_and_Islam Muslim-Christian relations], talked about Islam as a sect or as the heresy of the Saracens. However in the writings of Peter the Venerable the interpretation of Islam was basically negative.
With the help of some catholic orientalist like Louis Gardet, Georges Chehata Anawati, Giulio Basetti Sani and especially Louis Massignon, from the Second Vatican Council, with Nostra aetate and Lumen gentium, the catholic view on Islam turned in other direction. As regard Muslim, [http://www.vatican.va/archive/hist_councils/ii_vatican_council/documents/vat-ii_const_19641121_lumen-gentium_en.html Lumen Gentium] says: "the plan of salvation also includes those who acknowledge the Creator. In the first place amongst these there are the Muslims, who, professing to hold the faith of Abraham, along with us adore the one and merciful God, who on the last day will judge mankind".