[Esaias]

The two church "offices" are bishop (overseer) and deacon (minister/servant/assistant). Since each congregation was to have bishops, and each was to have elders (ordained elders), it seems the bishops (and possibly also the deacons) were the elders. So I don't see elders (presbyters) as a separate class from bishops and deacons.

This structure is essentially the same as first century synagogue structure except there is no "president" (that role being fulfilled by Jesus through His Spirit in the church).