King and Lord
All men are called to belong to the new people of God. Wherefore this people, while remaining one and only one, is to be spread throughout the whole world and must exist in all ages, so that the decree of God's will may be fulfilled…, that all His children, scattered as they were, would finally be gathered together as one. (Jn 11:52)) It was for this purpose that God sent His Son, whom He appointed heir of all things, (Heb 1:2) that be might be teacher, king and priest of all, the head of the new and universal people of the sons of God. For this too God sent the Spirit of His Son as Lord and Life-giver (cf. Creed). He it is who brings together the whole Church and each and every one of those who believe, and who is the well-spring of their unity in the teaching of the apostles and in fellowship, in the breaking of bread and in prayers. (Acts 2:42).
It follows that though there are many nations there is but one people of God, which takes its citizens from every race, making them citizens of a kingdom which is of a heavenly rather than of an earthly nature. All the faithful, scattered though they be throughout the world, are in communion with each other in the Holy Spirit… Since the kingdom of Christ is not of this world (Jn 18:36) the Church or people of God in establishing that kingdom takes nothing away from the temporal welfare of any people. On the contrary it fosters and takes to itself, insofar as they are good, the ability, riches and customs in which the genius of each people expresses itself. Taking them to itself it purifies, strengthens, elevates and ennobles them.
The Church in this is mindful that she must bring together the nations for that king to whom they were given as an inheritance, (Ps 2:8) and to whose city they bring gifts and offerings. (Ps 71:10; Is 60:4; Rv 21:2) This characteristic of universality which adorns the people of God is a gift from the Lord Himself. By reason of it, the Catholic Church strives constantly and with due effect to bring all humanity and all its possessions back to its source in Christ, with Him as its head and united in His Spirit.