"If Santa tries to scare me tonight, I'm gonna kick his a**, daddy," he said in a mock-baby voice.
"'Twas the night before Christmas... #BeCarefulSantaShesTough," he captioned it.
It has been a celebratory month for the actor, 43, who welcomed a daughter, Jasmine, with his girlfriend, Lauren Hashian several days ago. This is the second child for Johnson, who also has a daughter from a previous marriage.
"Christmas came early! Within minutes of being born she was laying on daddy's chest. And being a grateful man takes on a whole new meaning..." he wrote on Instagram after the baby was born. "Thank you guys so much for the awesome congratulatory wishes and love you've been sending @laurenhashianofficial and myself. We're extremely grateful."