The word "thee" is part of archaic English, as in, for example, the English of the King James Version of the Bible. It is therefore ironic that the usage of "thee" would get so muddled and sometimes outright wrong in a song sung by a Christian icon who goes back to a time when the King James Version was still a more predominantly used English Bible version than it is today. In such archaic English, "thee" was a more informal counterpart to "you" when that kind of English was current, corresponding to "informal' counterparts still preserved in a lot of other languages (for example in French the informal "te", versus the formal "vous", in Spanish the informal "te", versus the formal "Usted", and in German the informal "dich", versus the formal "Sie"). In the lyrics above, "thee" is twice correctly used, in the title phrase "thee I love", and also in the phrase "to kiss thee". But even so there is a catch involving the usage in the next to last line above of "your" in addressing the same person also addressed as "thee". The use of both the informal thee / thou / thy and the formal you / your were not correctly applied to the same person at anywhere near the same time. The informal might be applied to a child and the formal pronouns applied to the same person layer as a grownup, but variations between formal and informal would never correctly apply to the same addressee so close together in time, like here in the same song. But the most glaring grammatical absurdity here is the use of "thee" as if it were a nominative pronoun, since it is actually an objective pronoun. That could make this song seem like a self-parody. The correct nominative counterpart is "thou" as alluded to above. The phrases "Thee is mine" and "Thee pleasures me" are outright crass. The former is as absurd as saying "me am" instead of "I am" or "her is" instead of "she is" to "us are" instead of "we are". So to make all the grammar and usage consistent with the two otherwise correct occurrences of "thee" (in "thee I love" and "to kiss thee"), "Thee is mine" would need to corrected to "Thou art mine", "Thee pleasures me" would need to be corrected to "Thou pleasurest me" and "your bonnet, your cape, and your glove" would need to be changed to "thy bonnet, thy cape, and thy glove".