Your own self (singular).
"In his sermon about divine grace, the preacher addressed himself as Yourself to emphasize the majesty of the speaker."
Honorific alternative letter-case form of yourself, sometimes used when referring to God or another important figure who is understood from context.
Yourself is a compound word formed from the pronoun your and the reflexive suffix -self, which has been used together since Middle English to refer back to the person being addressed. The term entered modern usage as a direct combination of these existing elements without any shift in its fundamental meaning.