When Paul wrote isn't all that relevant to the question as the teaching undermined the faith because it robbed it of a future hope. Teaching that Jesus already has come and gone with the world still full of evil is a denial of the gospel as a hope for the whole world.
The second point is true, as accepting portions of a system does not make one an adherent. Though my point with that was more to express that the tolerance for different interpretations is wide but not unlimited.
There are some eschatological positions that rise to 1st order theological issues rather than being 2nd and 3rd order. These are where one crosses the line from heterdoxy into heresy through denial of essentials.
The second point is true, as accepting portions of a system does not make one an adherent. Though my point with that was more to express that the tolerance for different interpretations is wide but not unlimited.
There are some eschatological positions that rise to 1st order theological issues rather than being 2nd and 3rd order. These are where one crosses the line from heterdoxy into heresy through denial of essentials.
(Full Preterism)
1.) To deny a future second coming of Jesus Christ is a first order issue, a foundation of the Christian faith
2.) To deny a future resurrection of the believer is a first order issue, a foundation of the Christian faith.
(Full Preterism) Is Heretical, Simple