What is the invisible church?

The invisible church is the whole number of the elect, that have been, are, or shall be gathered into one under Christ the head.

Proofs

• The invisible church is the whole number of the elect, that have been, are, or shall be gathered into one under Christ the head. (Ephesians 1:10; Ephesians 1:22-23; John 10:16; John 11:52)

Note: This question is not normally included in the classic list of the Baptist Catechism, but is found in what is commonly called Keach's Catechism.