Ecclesiastical Use
By a decree of the Sacred Congregation of Ceremonial of 31 December 1930 the Holy See granted bishops of the Roman Catholic Church the title of Most Reverend Excellency (Latin, Excellentia Reverendissima). In the years following the First World War the ambassadorial title of Excellency, previously given to nuncios, had already begun to be used of other Catholic bishops. The adjective Most Reverend was intended to distinguish the religious title from that of Excellency given to civil officials.
The instruction Ut sive sollicite of the Holy See's Secretariat of State, dated 28 March 1969, made the addition of Most Reverend optional.
According to the letter of the decree of 31 December 1930, patriarchs too were to be addressed with the title of (Most Reverend) Excellency, but in practice the Holy See continued to address them with the title of Beatitude, which was formally sanctioned for them with the motu proprio Cleri sanctitati of 2 June 1957.
Cardinals, even those who were bishops, continued to use the title of Eminence.
In some English-speaking countries, the honorific of Excellency does not apply to bishops other than the nuncio. In English law, Anglican archbishops and bishops are granted the titles, respectively, of Grace (Your Grace, His Grace, as for a duke) and Lordship. The same titles are extended by courtesy to their Catholic counterparts, and continue in use in most countries that are or have been members of the Commonwealth. An exception is former British East Africa (Kenya, Uganda, Tanzania).
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