Editor of Q-News, a Muslim magazine
"The media are giving the supposed "anger of the Muslim nation" too much coverage. Such insults are as old as Islam itself. The Prophet dealt with them with dignity. We must stop over-reacting ...
"A Muslim who truly lives according to the moral code of Islam - of justice, neighbourliness and compassion - will know that it is our greatest weapon against misrepresentation. Perhaps the Pope was 'merely quoting' the 14th-century emperor. Perhaps he did so because he actually shares this belief. If so, he is more ill-informed than we thought. I refuse to let such provocations shape the global faith agenda."
Muhammad Abdul Bari
Secretary general of the Muslim Council of Britain
"The Muslim Council of Britain is deeply disturbed that the Pope ... quoted from the 14th-century Byzantine emperor Manuel II Paleologus. The emperor's views about Islam were ill-informed and frankly bigoted.
"One would expect a religious leader such as the Pope to act and speak with responsibility and repudiate the Byzantine emperor's views in the interests of truth and harmonious relations between the followers of Islam and Catholicism.
"Regrettably, the Pope did not do so and this has understandably caused a lot of dismay and hurt throughout the Muslim world. We would hope that the Pope will clarify his remarks without delay."
Director of the Council for Arab-British Understanding
"It is difficult to see anything positive coming from these comments. What was the Pope aiming to do by promoting the words of what he termed an "erudite" emperor who claimed that everything that Muhammad provided was "evil and inhuman"? There were infinitely more constructive ways to make his point about violence than to quote the rant of a 14th century emperor ... The previous Pope did much to try to win hearts and minds in the Islamic world. In one stupid line the Pope ... sent Muslim-Christian relations back decades. [He] needs to apologise at once. What is so sad is that while there have been acute political tensions between western and Islamic leaders, until now there had not been confrontation between mainstream religious leaders."
Author of Western Muslims and the Future of Islam
"He has said it before - that Muslims should tackle the issue of jihad and violence, but the way it was done was a bit clumsy.
"If you follow the whole lecture, though, his message is very worrying. He is saying we have to redefine what Europe is all about ... to reduce the past and neglect Islamic participation. Many Islamic values are in the west. All that we knew about Aristotle in the middle ages was coming from Averroes [the 12th-century scholar in Islamic Spain].
"It's worrying to say that Islam is disconnected from rationality."