Apostrophe catastrophe, # 16

Today, another apostrophe — or rather another gap where an apostrophe should be — in a prayer that was posted on Facebook, and which you can buy, with minor variations and less punctuation, as a poster at Zazzle:

Here, of course, Jesus needs a possessive apostrophe and a possessive s: Jesus’s. I’m not sure when and where the habit began of not adding the normal ’s to singular nouns ending in s, but it isn’t right, it isn’t clear, and it offers much opportunity for error and misunderstanding. The added possessive ending should also be pronounced…

The rules are covered in Oxford Dictionaries, under ‘Apostrophe’. However, I can’t agree with OxfordDictionaries about the correctness of exemptions to the rule (and I’m backed by both the British MHRA Style Guide and the North American MLA Style Manual on this): all singular nouns ending  in s, common and proper, should take a final s after the possessive apostrophe.

OxfordDictionaries offers St Thomas’ Hospital to exemplify the exemptions. Wikipedia points out that it was ‘usually known as St Thomas’s Hospital until the late 20th century’ — but why should some idiot’s grammatical fail be allowed to mar and mangle the moniker of an ancient institution?* I’ve never heard anyone pronounce it St Thomas’ Hospital (i.e. St Thomas Hospital) only St Thomas’s Hospital (St Thomasez Hospital).


* A brief history of the hospital can be found on The Old Operating Theatre: Museum and Herb Garret website, which points out that the hospital ‘was described as ancient in 1215’.