For follow-up discussion and general commentary on the topic. Comments are sorted chronologically.
Frederic A Parker
A note of clarification related to when the "church" was founded. Jesus founded the church almost immediately following the resurrection (John 20:19-23).
1. This is called the Johanine Great Commission.
2. This is when the disciples first received the eternal life and the inerrant insight provided by the Holy Spirit, as promised by Jesus earlier (John 16), and were commissioned and authorized by Jesus to act on His behalf. He later told them to remain in Jerusalem for the power to act. That power came into force at Pentecost (Acts 4).
3. In business terms, Jesus set up the initial structure of the new church and commissioned the officers here immediately following His resurrection and glorification. He spent the next several weeks giving them final instructions in preparation. The first public demonstration of the new church was at Pentecost (IPO, initial public offering).
4. This may be considered the break-point between the Jewish Age and the Christian Age, between the Old Testament and the New Testament.