John 8:31-32 HCSB
31 So Jesus said to the Jews who had believed Him, “If you continue in My word, you really are My disciples.
32 You will know the truth, and the truth will set you free.”
Not just hearing but continuing in the word is the mark of a disciple. It reminds us of things we know, teaches new things, and brings comfort to our hearts and the joy of our salvation. That is the truth, for He came in grace and truth.