This is the third promise of the coming of the Paraclete in the Gospel of John. Jesus had made the first promise in 14:16-17, and the second one in 14:26. The Paraclete or Advocate is sent by Jesus and the Father. The Paraclete is sent by Jesus, but is sent from the Father. The Paraclete is sent here to testify or bear witness to Jesus. This means that the teaching of the Paraclete will not be new teaching but a confirmation of what Jesus has already taught and done. Just as the Paraclete bears witness, so must the disciples, since they have seen and heard Jesus from the beginning. The Paraclete will give strength to the disciples in their time of trial so that they will not fall away. The Paraclete will work in and through the disciples. The work of Jesus continues through the Paraclete working in the disciples.
Because of this work of Jesus, the disciples will have to face persecution from those who do not accept them. As a matter of fact, those who engage in such persecution will think they are right and, by so persecuting the disciples, will think they are, in effect, worshipping God. This is because they have not understood the meaning of the incarnation and so, have not been able to recognize God’s unconditional and gratuitous love made manifest in Jesus. Jesus predicts these happenings, to both prepare the disciples in advance for what is to come and also, to warn them about the consequences of following him. Their perseverance and standing firm, even in the midst of persecution, will reveal their love for him and the Father and will be the tangible expression of their faith.
Believing in Jesus is not easy. It is one thing to verbally profess faith in him and another to live out all that he taught and did. It is especially difficult to follow him when things do not go the way we want them to and when things happen contrary to our expectations. When those to whom we are good repay us with goodness, we are not surprised, because we expect them to do just that. However, when those to whom we have reached out in love are ungrateful and sometimes openly hostile to us, we get shocked at their behavior, simply because we did not expect them to react in that way. It is at times like these that we must remember the predictions of Jesus made here. His love for the world, shown in the most tangible manner on the cross, was spurned by most of his contemporaries, yet that same love continues to be made new, even today, two thousand years later. We, too, are called not to fall away but to persevere in love.