Key elements of Christian doctrine are offensive to Muslims, the Archbishop of Canterbury has said in a letter to Islamic scholars.
Dr Rowan Williams also spoke critically of the violent past of both religions and Christianity’s abandonment of its peaceful origins.
His comments came in a published letter to Islamic leaders, intended to promote closer dialogue and understanding between the two faiths.
However they come just months after Dr Williams was forced to clarify comments in which he said some parts of Islamic law will “unavoidably” be adopted in Britain.
The comments are also made as the once-a-decade Lambeth Conference begins in Canterbury. Up to a quarter of bishops are boycotting the event, as the Anglican Church faces continuing division over the issues of women bishops and homosexual clergy.
The wide-ranging letter, which covers difficult issues including religious freedom and religiously-inspired violence is in response to a document written last year by Muslim scholars from 43 countries.
Discussing differences between the religions, Dr Williams acknowledges that Christian belief in the Trinity is “difficult, sometimes offensive, to Muslims”.
The Trinity is the Christian doctrine stating God exists as the Father, the Son and the Holy Spirit and conflicts with Islamic teaching that there is one all-powerful God.
Speaking about the history of the two religions, Dr Williams said they had been too often confused with Empire and control.
He said: “Despite Jesus’ words in John’s gospel, Christianity has been promoted at the point of the sword and legally supported by extreme sanctions; despite the Qur’anic axiom, Islam has been supported in the same way, with extreme penalties for abandoning it, and civil disabilities for those outside the faith.
“There is no religious tradition whose history is exempt from such temptation and such failure.”
He goes on: “What we need as a vision for our dialogue is to break the current cycles of violence, to show the world that faith and faith alone can truly ground a commitment to peace which definitively abandons the tempting but lethal cycle of retaliation in which we simply imitate each other’s violence.”
The 17-page letter, called A Common Word for the Common Good, is in response to a letter from Muslim leaders written last September.
That letter, A Common Word Between Us and You, was signed by 138 Muslim scholars to declare the common ground between the two religions.
Dr Williams described the Muslim document as hospitable and friendly and added: “Your letter could hardly be more timely, given the growing awareness that peace throughout the world is deeply entwined with the ability of all people of faith everywhere to live in peace, justice, mutual respect and love.”
His own dense and meticulous letter did not mention sharia Islamic law at all. He received widespread criticism from politicians and other clergy for his comments in February and later told the General Synod he took responsibility for his “unclarity” and “misleading” choice of words.