What's the difference between a Rev., a Rt. Rev., a Very Rev., and a Rev. Canon? Other than their same-sex relationships, of course ...
A Reverend is just an ordinary priest.
A Right Reverend is a bishop.
A Very Reverend is the Dean of a cathedral or seminary.
The Reverend Canon is a Canon (associate priest) of a Cathedral.
After we crossed the Tiber, I called the archbishop "Your Grace" without thinking . . . which is correct for both Anglican and Catholic archbishops in Britain . . . but not in the U.S. (he is apparently "Your Excellency" here . . . cardinals are "Your Eminence" everywhere. One of my dad's friends who is a judge addresses other judges as "Your Eminence" . . . just a personal quirk.)
Archbishop of another Province The Most Revd the Lord Archbishop of
Bishop of London The Rt Revd and Rt Hon the Lord Bishop of
Diocesan / Suffragan Bishop
Either The Rt Revd the Lord Bishop of
Or the Rt Revd the Bishop of
Assistant / Retired Bishop
The Rt Revd J.D.Smith (or John Smith)
Dean
The Very Revd the Dean of
Provost
The Very Revd the Provost of
Archdeacon
The Ven the Archdeacon of
Canon
The Revd Canon J.D.Smith (or John or Jane Smith)
Prebendary
The Revd Prebendary J.D.Smith (or John or Jane Smith)
Rural Dean
No special form of address (The Revd, the Revd Canon, etc)
Dean of Oxford / Cambridge College
No special form of address
Cleric also Professor
Either The Revd Professor J.D.Smith
Or Professor the Revd J.D.Smith
Canon also Professor
Either The Revd Canon Professor J.D.Smith
Or Professor the Revd Canon J.D.Smith
Cleric also Doctor Either
The Revd Dr J.D.Smith
Or The Revd J.D.Smith (degree)
Canon also Doctor
The Revd Canon J.D.Smith (degree)
Other Clergy / Priest / Deacon
The Revd J.D.Smith (or John or Jane Smith)
The following points should be noted particularly:
A diocesan or suffragan bishop has a title conferred on him by his consecration or subsequent translation, which he is entitled to hold until he resigns. He then reverts to his personal name, retaining the title 'Right Reverend'.
A dean, provost or archdeacon has a territorial title until he resigns. He then reverts to his personal name, and his title is 'Reverend' unless the rank of dean, provost or archdeacon emeritus has been awarded.
Retired archbishops properly go back to the status of a bishop but may be given as a courtesy the style of an archbishop.
A bishop holding office as a dean or archdeacon is addressed as The Rt Revd the Dean / Archdeacon of.
If a cleric's name or initials are unknown, he or she should be addressed as The Revd - Smith or the Revd Mr / Mrs / Miss / Ms Smith. It is never correct to refer to a cleric as 'The Reverend Smith' or 'Revd Smith'.
There is no universally accepted way of addressing an envelope to a married couple of whom both are in Holy orders. We recommend the style 'The Revd A.B. and the Revd C.D.Smith'.