Anyway, the Sadducee scribes are upset because Anointed Jesus forgave Zealot Jesus. Only God (θεός), they say, can do this. But Anointed Jesus is both a High Priest, and an agent of Caesar, so he has the authority to forgive sins regardless if one considers θεός to be Caesar or יְהוָה, but the scribes either don’t recognize this or disagree with this choice. The interaction between Jesus and the scribes is a question of authority. If the scribes consider his status as High Priest as having lapsed, then perhaps they don’t realize the connection between Anointed Jesus and Caesar, it’s unclear in the passage. Perhaps the scribes were unwilling to forgive a Zealot.
From a narrative perspective, it’s important to realize that this verse and the prior one go beyond an eyewitness style account to speak of what the scribes were thinking.