To be “in” the word of Jesus is a whole new life. This is what it is to be a true disciple. To live “in” the word of the riches of the word of Jesus.
How are abiding in his word and truly being his disciple related to each other?
“If you abide in my word, you are truly my disciples.” Jesus is saying that the mark of the true disciple is lasting, enduring, persevering, keeping on in the force field of the word. Temporary tastes of the truth and beauty and value and power and grace and bread and water and brightness of the word do not make you a Christian. The mark of Christians is that we taste and we stay.
To whom shall we go? You, O Lord, have the words of life (John 6:68).
But Jesus does not simply say that true disciples are in his word. He says they “abide” in it. So our fourth question is:
Which is why when you get to chapter 15, Jesus can say, not only “abide in my word,” but “abide inme.” “If anyone does not abide in me he is thrown away like a branch” (John 15:6).
So the answer to our second question would be: The phrase “my word” here in John 8:31 (“if you abide in my word”) refers to the sum of Jesus’ teaching which is summed up in himself and all that he is for us as the crucified and risen Son of God.
WE must Know Jesus Through His Word.