1 sn The plural pronoun their makes it clear that Jesus was responding to the faith of the entire group, not just the paralyzed man.
2 sn The passive voice here is a divine passive (ExSyn 437). It is clear that God does the forgiving.
3 sn Now Jesus put the two actions together. The walking of the man would be proof (so that you may know) that his sins were forgiven and that God had worked through Jesus (i.e., the Son of Man).
4 sn The term Son of Man, which is a title in Greek, comes from a pictorial description in Dan 7:13 of one “like a son of man” (i.e., a human being). It is Jesus’ favorite way to refer to himself. Jesus did not reveal the background of the term here, which mixes human and divine imagery as the man in Daniel rides a cloud, something only God does. He just used it. It also could be an idiom in Aramaic meaning either “some person” or “me.” So there is a little ambiguity in its use here, since its origin is not clear at this point. However, the action makes it clear that Jesus used it to refer to himself here.
5 sn Jesus did not finish his sentence with words but with action, that is, healing the paralytic with an accompanying pronouncement to him directly.