October 7. On this date in 1973, the Universal House of Justice wrote an NSA that "Many of the Tablets of Bahá'u'lláh and Abdu'l-Bahá are in exalted and highly poetic language in the original Persian and Arabic and you will see, for example, that when translating Bahá'u'lláh's Writings into English the beloved Guardian did not use present-day colloquial English but evolved a highly poetic and beautiful style, using numbers of archaic expressions reminiscent of the translations of the Bible."

October 7. On this date in 1973, the Universal House of Justice wrote an NSA that "Many of the Tablets of Bahá'u'lláh and Abdu'l-Bahá are in exalted and highly poetic language in the original Persian and Arabic and you will see, for example, that when translating Bahá'u'lláh's Writings into English the beloved Guardian did not use present-day colloquial English but evolved a highly poetic and beautiful style, using numbers of archaic expressions reminiscent of the translations of the Bible."

This practice of using 17th Century English in order to mimic the language of the King James Version of the Bible has continued with translations commissioned by the Universal House of Justice.
For example, William McElwee Miller and Earl E. Elder's translation of the Kitáb-i-Aqdas was published by the Royal Asiatic Society with the title Al-kitab al-aqdas or The most holy book in 1961, some thirty years before the Bahá'í Administrative Order's authorized translation in 1992.

What I particularly like about Elder & Miller translation is that it uses contemporary English. The 1992 translation commissioned by Universal House of Justice unnecessarily uses words like "hath," "heareth," "thy," and "ye" in an attempt to mimic the tone of the King James Version of the Bible.
In 1973 a "Synopsis and Codification" of the Kitáb-i-Aqdas was published in English by the Universal House of Justice, with 21 passages of the Aqdas that had already been translated into English by Shoghi Effendi with additional terse lists of laws and ordinances contained in the book outside of any contextual prose.

The Aqdas was only officially translated into English in 1992, by which time other translations were becoming increasingly available through dissemination via the internet.

My personal opinion is that the material in the Kitáb-i-Aqdas is so objectionable that the Bahá'í authorities wished to shield Western believers from its contents, as they do from Bahá'u'lláh's other works by not providing translations.

370. Translation of Bahá'í Literature into Everyday Language-- Simplifications and Paraphrasing Not to be Published as Scripture
"The Universal House of Justice, in response to your letter of 20 April concerning translations into French or Creole using simpler words than the original text, has requested us to send the following three quotations. These make it clear that a quotation in English may be rendered into simple English in order to facilitate its translation into another language or dialect. However, it is not permissible to publish simplifications and paraphrased extracts of Bahá'í Writings as Bahá'í Scripture.
'We have noticed a tendency in a number of countries to attempt to translate Bahá'í literature into the current, easy, everyday language of the country. This, however, should not be an overriding consideration. Many of the Tablets of Bahá'u'lláh and Abdu'l-Bahá are in exalted and highly poetic language in the original Persian and Arabic and you will see, for example, that when translating Bahá'u'lláh's Writings into English the beloved Guardian did not use present-day colloquial English but evolved a highly poetic and beautiful style, using numbers of archaic expressions reminiscent of the translations of the Bible.' (From a letter dated 7 October 1973 written by the Universal House of Justice to a National Spiritual Assembly)
'Obviously teaching literature and books about the Faith can be written in simple English. However, we feel that when the Sacred Writings are published the standard English translation should be used, but there would be no objection to printing alongside it the translation into simple English which should be described as a paraphrase of the Holy Word. Thus, for the people of ... who have difficulty in comprehending standard English, the simple English version would be in the nature of an explanation of the Writings which they could understand. In the case of teaching literature in which quotations from the Writings appear, these could either be paraphrased or a simple English version could be used with the standard version printed as a footnote. This method would also provide a means whereby the people of ... could improve their knowledge and understanding of the English language.' (From a letter dated 20 September 1973 written on behalf of the Universal House of Justice to a National Spiritual Assembly)
'It is, of course, permissible to translate Bahá'í Writings into other languages and dialects of languages. It is also possible to simplify or paraphrase the Bahá'í Writings in order to facilitate their translation into languages and dialects having small vocabularies. However, it is not permissible to publish simplifications and paraphrases of Bahá'í Writings as Bahá'í Scripture.'" (From a letter dated 13 March 1969 written on behalf of the Universal House of Justice to a National Spiritual Assembly)
(From a letter written on behalf of the Universal House of Justice to the Spiritual Assembly of Guadeloupe, May 13, 1986)