In 1843 Joseph taught that “Where the oracles of God are revealed there is the kingdom of God.” and “Wherever the Oracles of God are received & found there is the Kingdom of God.” (Words of Joseph Smith, p. 159) I wasn’t sure what the word “oracles” meant, so I looked it up in a 1828 dictionary. It states,
“Among christians, oracles, in the plural, denotes the communications, revelations or messages delivered by God to prophets. In this sense it is rarely used in the singular; but we say, the oracles of God, divine oracles, meaning the Scriptures.”
To me that implies that the Kingdom of God is established on earth any time He speaks to someone.
The Prophet continued, “What constitutes the kingdom of God? an administrator who has the power of calling down the oracles of God, and subjects to receive those oracles no matter if there are but 3, 4, or 6 there is the kingdom of God &c.” (ibid)