Ultimately, the problem with Docetism is its insistence on denying the fundamentals of the faith - from the Incarnation to the Crucifixion to the Resurrection. All of these have negative salvific implications and all of these heresies (in some form or another) are alive and well today.
This is why it behooves us so to study Docetism. The fruits of this study are many; for one, it can help the reader understand John’s epistles better. It teaches us more about the early church fathers and allows us to trace a few trajectories of the Roman Catholic Church. It also gives is a clearer picture of Gnosticism as a whole and the threat it posed to the young church.
Currently, a healthy grasp of Docetism is vital because modern day critics are twisting history in order to prop up a ridiculous hypothesis – if it even deserves to be called that – namely, that the man Jesus of Nazareth never even existed. This last topic is what initially sparked my interest in this area.
Looking back on the positive fruits in my own life from studying this portion of early church history and its theological ramifications - I can honestly say that I am glad that it did spark my interest. For this, I guess I owe Satornilus one.