"When Jesus, who had suffered the death of the cross for mankind, had risen, He appeared as the one constituted as Lord, Christ and eternal Priest, and He poured out on His disciples the Spirit promised by the Father. From this source the Church, equipped with the gifts of its Founder and faithfully guarding His precepts of charity, humility and self-sacrifice, receives the mission to proclaim and to spread among all peoples the Kingdom of Christ and of God and to be, on earth, the initial budding forth of that kingdom. While it slowly grows, the Church strains toward the completed Kingdom and, with all its strength, hopes and desires to be united in glory with its King."
January 1, 1970
https://en.wikiquote.org/wiki/Lumen_gentium