LONDON — A couple of years ago, I had an encounter with the Archbishop of Cant, as his critics privately call him It was at the British Academy, where His Grace had been lecturing a roomful of historians on the subject of “the other” — a pretentious way of referring to remote historical figures, which segued into a disquisition on how the British ought to treat Muslims.

According to Archbishop Williams, it was quite wrong to impose Judaeo-Christian cultural norms on “the other” in the name of a moral absolutism that was quite inappropriate in a modern multicultural society like Britain.

He had particularly harsh words to say about Pope Benedict XVI, who had then recently been elected, and whose devastating attack on “the dictatorship of relativism” was still ringing in our ears. For the leader of the Anglican Church, it seemed, for the Pope to lay claim to any moral certainty or theological truth was at the very least lacking in respect for “the other.”

After the archbishop had finished, I rose to reply. I was angry, probably too angry for it to have been wise to speak in a semi-public colloquium. But I didn’t care.

“Nobody is as absolutist as a relativist,” I said. Looking him straight in the eye, I added: “And nobody is as relativist as an archbishop.”

There was an audible gasp. Such disrespect for the successor of Augustine and Anselm, of Becket and Langton, of Cranmer and Laud would once have caused the culprit to have his ears cropped. Even today, my remark had offended against the niceties of academic discourse in its inner sanctum — the British Academy. Some sort of retribution, if only verbal, was surely called for.

But Archbishop Williams merely beamed. “I think we really agree,” he declared.

This is the man who has just sold the pass on perhaps the most important legacy of Judaeo-Christian jurisprudence: the idea that every person is equal in the sight of God, and hence also equal before His law. Human, secular law reflects its origins in the Ten Commandments and the Sermon on the Mount, both of which embody the fact that God loves all humanity, the proof of which is the fact that He has given us the law.

Sharia law knows nothing of equality for women or non-Muslims. Its imposition in countries where Islam competes with Christianity has led to persecution on a vast scale. Archbishop Williams does not seem to care about this.

Nor does he care about the damage the affair has done to the authority of his church. Elizabeth II, who is supreme governor of the Church of England, has let it be known that she is deeply concerned about this aspect of the controversy, while keeping her views about the substance of the archbishop’s remarks to herself.

Just as all seemed lost, the British establishment closed ranks. On Monday, the archbishop had to open the general synod, or governing assembly, of the Church of England. no sooner had he entered the hall than almost all those present rose to give him a standing ovation. His speech, billed as an apology, was actually a piece of effrontery. He denied that he had advocated “parallel” status for Sharia, then proceeded to make the case for “certain additional choices” to be offered to Muslims to resolve their legal disputes. Despite, or perhaps because, of his lack of logic, he got a second ovation when he sat down.

Meanwhile Prime Minister Brown let it be known that he had phoned to give the archbishop, “a man of great integrity,” his support. The state had come to rescue of the established church. By Tuesday the press had moved on.

Yet this episode has a lasting significance. Those who follow this column will be aware that Sharia law already operates in Britain: not only in civil, especially marriage, law, but even in minor criminal cases, where both sides agree compensation without involving the secular courts.

Issues that never surface in public for fear of offending Muslims, such as the de facto legalization of polygamy, the prevalence of “honor killings” and female genital mutilation, or the epidemic of birth defects caused by first cousin marriage, are now being openly debated.

The spectacle of the Church of England and its leader advancing the cause of Sharia will not be soon forgotten. The archbishop’s adviser on Islamic affairs is reported to be Tariq Ramadan, the Oxford-based academic who is banned from America because he has links to the Muslim Brotherhood and other Islamists.

Professor Ramadan is fond of reacting to criticism of Sharia by accusing the critics of fomenting “Islamophobia.” What the Archbishop of Canterbury has unwittingly revealed, however, is that people are not impressed by this tactic. They can see how Sharia is practiced in Africa, Asia, and the Middle East, and they want none of it. They are beginning to notice how badly their leaders have misled them.

The row has blown over, but the Islamists have been emboldened. Secularists may count this a triumph, but it is a Pyrrhic victory. For if the ramparts of Christianity are overrun by the angry young men of Islam, who will be more vulnerable than those who have no faith?