Here we don’t learn any more about the source of the sin, but we learn a bit about the mechanics of it. Here, Jesus forgives the sins of the paralytic, and this causes some commotion among the scribes present.
[record scratch] Wait, there were scribes just hanging around the house that was so crowded they just had to lower someone in through the roof? These would have been Sadduceean scribes, and not just passing through, but sitting there in the company of Jesus. By association, then this is a room full of Sadducees, and possibly some Herodians, and Jesus is there as a leader, teacher, and probably high priest. This is clearly Anointed Jesus.