Bishop Michael Nazir-Ali criticised an article written by Mohammed bin Nawwaf bin Abdulaziz, Saudi Arabia's Ambassador to the United Kingdom, in which he claimed his country is vital to UK security.
"What he doesn't say is that the rulers are an unelected oligarchy who subscribe to a Wahhabi interpretation of Sharia not shared by many other Muslims," said Bishop Michael in a letter to the Telegraph.
He added: "He says nothing about how Islamic jurists have discovered important principles of movement in Islamic law which have allowed them to take account of the common good of a community.
"He doesn't say how in the last 100 years or so, Islamic scholars have tried to limit the scope and implementation of the draconian punishments which are commonplace in Saudi Arabia."
The original article by the Saudi ambassador said: "Just as we respect the local traditions, customs, laws and religion of Britain, we expect Britain to grant us this same respect. We do not seek special treatment, but we do expect fairness."
He was responding to a UK decision to scrap a deal to train Saudi prison staff.
"The Kingdom's contribution to Britain's security and economy provides the foundations on which the bilateral relations between our two countries are built, allowing trade, cultural exchanges and military cooperation to flourish," the ambassador added.
But Bishop Michael said: "Gulf security may be our security but it must be founded on respect for fundamental freedoms and humane treatment of fellow human beings, if it is to be moral and permanent. Otherwise, what are we securing?"