Title of Christ (1 John, 2:1).
The Greek word, parakletos, so rendered is the same as that transcribed Paraclete in Saint John's Gospel, 14, where Our Lord promises to send "another Paraclete" (advocate), the Holy Ghost.
Christ as Advocate defends the cause of Christian believers against their accuser, the devil (Apocalypse, 12).
He is called in 1 John 2, a just advocate:
He claims that the virtue of His satisfaction be extended to all in fellowship with Himself.
The word, which literally means "one called to one's side" to strengthen and plead, implies that the Christian effectually seeks His help.
New Catholic Dictionary