What does "Church" Mean?
Response to comment [from a Catholic]: "What does "Church" Mean?"
"A group or assembly of persons called together for a particular purpose. The term appears in only two verses in the Gospels (Mt 16:18; 18:17) but frequently in the book of Acts, most of the letters of Paul, as well as most of the remaining NT writings, especially the Revelation of John..." Full text: Church, Elwell, W. A., & Comfort, P. W. (2001). In Tyndale Bible dictionary. Wheaton, IL: Tyndale House Publishers.
Response to comment [from a Christian]: "Who have you been taught authored the Book of Hebrews?"
See:
Hebrews Introduction & Outline J. Vernon McGee