The Definition of a Church
A church is defined as an “assembly called out from within”. This is first seen in the Old Testament with the Tabernacle, which God called the church in the wilderness (Acts 7:38). From the Nation of Israel (a type of the kingdom) God called the tribe of Levi (a type of born again sanctified believers) to serve Him in the tabernacle (where His presence dwelt). He divided the Levites into 3 groups and set the house of Aaron over the whole assembly. The work of the Tabernacle was to bring glory to God through the offerings and sacrifices, which all pointed to Christ. Only those whom God called to service in the Tabernacle were part of it. This is a visible, local called out assembly which was to bring glory to the coming Messiah.
A New Testament Church consists of people who have first been Born Again into the Kingdom of God, who are then willing to publicly declare Christ through Baptism (the beginning of sanctification), and willing to set themselves apart from the world (the continuance of sanctification). These believers are then called and placed into a local assembly for the purpose of glorifying Christ in the world.
In Heaven there will be an assembly of believers called out from within the general assembly of believers that will sit in the throne room of God and bring glory unto Him. (Ephesians 3:21, Hebrews 12:22-23, Revelation 3:12).
There is not a single instance in the Scriptures where a body of believers referred to as a church encompasses all believers. Not in the Old Testament, the New Testament, nor in Eternity. Therefore I cannot agree with the idea of a “universal” church.