Another shout of praise goes up to Jehovah!, page-2897

"Jesus makes zero reference"
Yes, because the teachings of Christ THROUGH Paul are the "MYSTERY"
https://doctrine.org/pauls-mystery

The Mystery (μυστήριον)

The word translated “mystery” is the Greek word μυστήριον. This unfortunate translation has confused most of Christendom. The word μυστήριον does not mean “mystery” as we think as in “strange,” “enigma,” “weird,” etc. It means a “secret”–something kept hidden, something previously unrevealed. Paul used the term to describe the body of doctrine the risen, ascended, glorified Lord revealed to him. God alone can keep a secret and He had kept these revelations hidden until He chose to disclose them. Paul called these doctrines “secrets” for that was what they were. What were these secrets that Peter and the other apostles knew nothing about?