Whoever refuses honour to the Son refuses honour to the Father who sent him.
This is part of how Jesus responds to those who question his actions such as healing on the Sabbath in John 5:17-30. It struck me that a similar sending by Jesus will carry the same duty. So the Apostles are sent, Simon Peter in a particular way with the keys, Paul to the Gentiles, and so on. But there's more: these Apostles, of whom Jesus said "he who hears you hears me; he who rejects you rejects me, and he who rejects me rejects the one who sent me" (Lk 10:16), in their turn sent their successor bishops, who in their turn sent successor bishops as well as ordained priests and deacons. Is there not also a duty to them?