In John 14-17, the promise that God would send the paraclete (Comforter, Advocate) looms large on the horizon. The fact that Jesus describes the Advocate as his personal representative could qualify that role as being the most important work of the Spirit. And that Advocate is said to accomplish three things:

John 16:7 (NIV): 7 But very truly I tell you, it is for your good that I am going away. Unless I go away, the Advocate will not come to you; but if I go, I will send him to you. 8 When he comes, he will prove the world to be in the wrong about sin and righteousness and judgment: 9 about sin, because people do not believe in me; 10 about righteousness, because I am going to the Father, where you can see me no longer; 11 and about judgment, because the prince of this world now stands condemned.

Each of the three items deserve special attention:

1. Sin. In his Daily Study Bible volume on John, William Barclay argues that what Jesus is referring to is the fact that those who killed Jesus thought they were doing God a service. It was only after the resurrection and as a result of the work of the Spirit in the Pentecost experience that they became convicted of sin – “cut to the heart,” to quote the NIV of Acts 2:37. It is still the work of the Spirit to convict humans of sin.

2. Righteousness. Why would the truth about righteousness be linked with the fact that Jesus would be going to the Father and would no longer be visible? Jesus’ presence with the Father would leave the work of conviction of righteousness to the Spirit. And it was an astonishing development that a condemned Jewish criminal would be the source of saving righteousness.

3. Judgment. The judgment here is first the judgment of Satan. Luke 10:18 quotes the words of Jesus when the 72 came back from their mission trip during which they had accomplished miraculous things: “I saw Satan fall like lightning from heaven.” This would link up with the war in heaven as described in Revelation 12:7-12 where Satan is cast out from heaven in a final sense at the cross (vs. 10). And how does the judgment relate to the believer? Zechariah 3:1-6, Satan stands as the accuser of Joshua the high priest. But the Lord rebuked him – and clothed him with fine garments, representing a righteousness which is granted him but is not his own.

The Holy Spirit and Hope. Both Romans 8 and 2 Cor. 5 point out the work of the Spirit in assuring believers of the hope of salvation and eternal life:

Romans 8:22-27 (NRSV): 22 We know that the whole creation has been groaning in labor pains until now; 23 and not only the creation, but we ourselves, who have the first fruits of the Spirit, groan inwardly while we wait for adoption, the redemption of our bodies. 24 For in hope we were saved. Now hope that is seen is not hope. For who hopes for what is seen? 25 But if we hope for what we do not see, we wait for it with patience.

26 Likewise the Spirit helps us in our weakness; for we do not know how to pray as we ought, but that very Spirit intercedes with sighs too deep for words. 27 And God, who searches the heart, knows what is the mind of the Spirit, because the Spirit intercedes for the saints according to the will of God.

2 Cor. 5:1-5 (NRSV): 1 For we know that if the earthly tent we live in is destroyed, we have a building from God, a house not made with hands, eternal in the heavens. 2 For in this tent we groan, longing to be clothed with our heavenly dwelling— 3 if indeed, when we have taken it off we will not be found naked. 4 For while we are still in this tent, we groan under our burden, because we wish not to be unclothed but to be further clothed, so that what is mortal may be swallowed up by life. 5 He who has prepared us for this very thing is God, who has given us the Spirit as a guarantee.

In sum, Scripture presents the Spirit as the one responsible for virtually all divine-human contact. The Spirit is presented as a personal being, capable of being everywhere present, a concept that we cannot fathom, given our human limitations. But as the representative of our Lord Jesus Christ, he reminds us that God will grant us all that we need.