The meaning of the news that the Kingdom of God is already reigning lies in the fact that God's reign does not appear as some overt, political, or external order, but rather is manifested from within—in the hearts of believers, in the lives of those who accept God's will.

The Internal Kingdom

The meaning of the news that the Kingdom of God is already reigning lies in the fact that God's reign does not appear as some overt, political, or external order, but rather is manifested from within—in the hearts of believers, in the lives of those who accept God's will. Thus, it is the announcement that the true kingdom represents an inner transformation of the individual, spiritual renewal, and a life filled with grace. It does not depend on external changes nor is it realized through violent overthrow, but is achieved through spiritual labor that transforms each person’s life.

As for the bearer of this good news, it is recognized that its transmission is entrusted to the Lord Jesus Christ Himself, who, blessing the Apostles, commanded them to preach: “Preach that the Kingdom of Heaven is at hand” (Matt. 10:7) – it is precisely this command that signifies that the good news is delivered by the One Who came to earth and then by His confessors, apostles, and the entire church, who, through baptism, communion, and benevolent service, spread God's presence among people. In other words, the bearers of this message are those who have accepted the Kingdom in their hearts and live by God's commandments, thus becoming “the Kingdom of God” within themselves and in their community.

Supporting citation(s):
“The Lord Jesus Christ, blessing the Apostles for preaching, said: ‘Preach that the Kingdom of Heaven is at hand.’ … Only true confessors of the Lord are given to understand that the Kingdom of God will not come in an observable manner, for it is within us (Luke 17:21).” (source: link txt)

“Two religious experiences – the nearness of the End and the nearness of the Kingdom – … ‘The time has come, and the Kingdom of God is at hand; therefore, repent and believe the Blessed News.’” (source: link txt)

“The Kingdom of God is already among the people. Everything begins with the acceptance of the Kingdom of the Lord in our hearts, open to God's will. This is the true beginning of the Kingdom of God.” (source: link txt)

Thus, the news that the Kingdom of God is already reigning means that God's grace and order have begun to work in the world through the transformation of the hearts of believers, with its bearers being both the Savior Himself and His followers, who, by accepting and spreading this good news, create a new humanity in Christ.