It is my understanding that "thee," "thy," and "thou" are second person, singular and "ye" and "your" are second person plural. That is to say they are the familiar forms and thus connote intimacy. The quakers, for example, insisted on continuing to use them when addressing each other for that very reason. And Cranmer and the translators of the King James version used the "thee" forms for that same reason.
When, however, the "thee" form is used today it is taken to connote formality, the very opposite of intimacy. Although I know the "thee" forms connotes intimacy, I don't feel that connotation, and I have used that language all my life. It feels formal. And yet I prefer the traditional language in general for all those reasons you spelled out. But I want to be intimate in my prayer to our heavenly Abba, and "you" [in the singular] feels intimate and, in fact, in modern usage it is. Subjectively, I am in a dilemma.
What generally is found in the KJV and the BCP is a careful distinction between the singular and the plural in terms of addressing persons and speaking of persons. So if there is one person it is "thou art" and if there are several it is "you are". In this the original texts are followed for they themselves so distinguish. By the time we get to the 20th century and the RSV this rule is only adhered to when the Person is God. When the person is a human being the rule is to follow the standard English of the 1950s and use "You." The problem then becomes (for those who have not Greek or Hebrew) of knowing when the "you" is one person or more than one person - and exegetically this is often important.
It will be recalled that most European languages to this day in their standard forms distinguish the second person singular from the second person plural. In English the trend not to distinguish them actually began before the KJV was translated and thus we can say that the KJV & BCP tradition of translation of carefully distinguishing the singular and plural was deliberate and against the trend.
I do not think that the matter of intimacy or formality arises in either the KJV or the BCP use of "Thee/Thou." These words are used strictly speaking to translate what in other languages is the second person singular. Thus both God and man are so addressed. It may be that the idea of intimacy comes to mind because of the use of the
second person singular in modern French as a way of expressing intimacy in family and between lovers. The Quakers as I understand were simply speaking the language of the KJV and in doing so they were not alone. My father's generation of coal-miners and agricultural workers from Yorkshire also spoke in that way amongst themselves. They wanted to be direct in speech and thus be clear when they spoke to one and when they spoke to "you-all"!
But the fact is that the language of the KJV & the BCP created the English way of prayer and thus God was addressed by each and all as "Thou art." from the late medieval period through to the 1960s; and so strong was this that the RSV kept to it in the 1950s, even though it used "you" of human beings. So did hymnwriters of that period.
Intimacy with the Father through the Son and by the Holy Ghost is relational and a gift and I do not think that it has anything to do essentially with the second person singular. After all those in this holy relation cry out "Abba, Father" and were taught by our Lord to pray "Our Father."
God as the THOU both is transcendent and also immanent and even as his pure holiness drives us away his love and the shed blood of Jesus draws us near.
Thus I say again that there was a major revolution in the 1960s when the accumulated experience and wisdom of addressing God was discarded in favour of new forms that were supposed to be relevant. In fact in the 1970s at an interview for a senior position I was asked, "When you pray alone how do you address God?" I knew that when I said "In the second person singular" I was ruling myself out of consideration! I still pray in the form I did in the 1970s and I see no reason to change. However, I do not claim that people who use the "you" form are inferior or heretical. I think that they are missing out in terms of inclusion in a great tradition!
The idea of intimacy or of formality never occurs to me with respect to the second person usage. It may be that the cosiness of some modern choruses and ditties used in some churches is intended to bring God near to us and we to God. Certainly he/she is addressed in familiar terms as if she/he were just like one of us! I am afraid that this approach worried me theologically rather than linguistically.
The Rev'd Dr. Peter Toon
Minister of Christ Church, Biddulph Moor,
England & Vice-President and Emissary-at-Large
of The Prayer Book Society of America