If by “diversity´ in a Christian context, one means things like diverse styles of worship or diverse church architecture, then perhaps diversity is a gift.

If by “diversity” one means a multiplicity of religions such as Islam, Christianity and Hinduism, then diversity is an unwanted gift. If the claims of Christianity are true, then all other religions have, to a large degree, got it wrong; their followers are deceived and their good works, insofar as they don’t lead to salvation, in vain.

Unfortunately, Justin Welby appears to be using “diversity” in the latter sense.

From here:

Archbishop Justin told his audience that diversity was a “gift not a threat” and he did not want to live in a “monocultural” society. He said he “rejoiced” in the example of inter faith co-operation and community work he had witnessed in Southall.

Archbishop Justin was speaking after visiting St John’s Church, the Shree Ram Mandir Hindu Temple and the Sikh Gurdwara Sri Guru Singh Sabha, where 20,000 free meals are served every week in Southall. He also met Muslim leaders, currently observing the Ramadan fast, at the Central Jamia Masjid Mosque in Southall.