Dr Rowan Williams is on course to become one of the most powerful Archbishops of Canterbury since the Reformation, under a programme of centralisation planned for the Church of England.

Under the plans, to be debated at the General Synod tomorrow, the Church bodies responsible for education, mission and finance will be abolished. The powers of the Church’s main boards and councils will instead pass to the archbishops of Canterbury and York.

However, The Times has learnt that some of the senior clergy and laity in the Church of England are planning to revolt against the shift of power from the democratically elected General Synod. The rebels will warn the synod in York that the centralising changes would turn the established Church into a medieval style of government more akin to a “Muslim-style theocracy”.

The radical plans have been drawn up as part of a series of measures designed to create a leaner Church better fitted to cope with falling attendances, a pensions black hole and plummeting asset values.

The synod is also to debate cutting the number of bishops at a time when the future of the dioceses of Wakefield, Bradford, Ripon and Leeds, Sheffield, Ely and Peterborough are being reviewed. It is possible that at least one diocese will disappear. The post of one bishop, the suffragan in Hulme, Manchester, has already been axed.

The changes are set out in a report to the synod which says the present system of boards, councils and committees is “too complex, cumbersome, costly and confused”.

The report claims the aim is to create “greater clarity” of responsibility and accountability.

The new structures are intended to be in place by the end of May 2011.

The Rev Chris Sugden, secretary of the evangelical group Anglican Mainstream and a member of the synod for the Oxford diocese, said: “This takes us back to a medieval church run by the clerics. The whole point of the Reformation was to make Parliament part of the government of the Church of England.

“It is much like the style of governance of the Orthodox churches, like the Muslims. It cuts out lay people.”

Clive Scowen, a lay Synod member, warned: “This represents the removal of a democratic strand of Church government. The long-term danger is that what is said on behalf of the Church becomes less representative of ordinary Christians.” The Rev Paul Perkin, vicar of St Mark’s, Battersea Rise, in the Southwark diocese, said: “There needs to be wider representation of ordinary members in the pews.”

The reforms come amid a £352 million shortfall in clergy pensions and after the Church Commissioners, who manage the Church of England’s investments, announced that the value of its portfolio shrank to £4.4 billion during 2008 compared with £5.7 billion the year before.

In 2008, the commissioners spent £7.3 million maintaining diocesan bishops’ houses and £14.5 million in grants for bishops’ support staff, office and working costs. This amounted to £500,000 per diocese on average, or ten clergy or lay worker stipends.

The financial crisis has forced the Church to turn to its members, who are to be told to more than double their giving. They should aim at giving away 10 per cent of their after-tax income, the synod will be told, donating 5 per cent “to and through” the Church and a similar amount to other work that helps “build God’s kingdom”.

Members currently give £600 million a year and provide more than half of the total cost of funding the Church of England. The rest comes from property and investment income.