In his upper room discourse, Jesus has already spoken of the Holy Spirit as helper and friend 14:16ff, in our passage for study he speaks of him as the prosecutor who convicts sinful humanity, and as the teacher of the people of God.

v5. Jesus has just touched on the theme of suffering, and now he announces to his disciples that he is going to the one who sent him. The disciples seem more concerned at his leaving than as to where he might be going.

v6. The thought of his going has filled the disciples with grief.

v7. Jesus tells the disciples that it is for their good that he goes away. The "good" ("it is expedient") is the coming of the Holy Spirit.

v8. This is the only passage of scripture which speaks of the Spirit's particular work in the "world". He will prosecute and bring about the world's conviction. Through the disciples' inspired preaching the world will know about sin, justice and judgment.

v9. The Holy Spirit will expose the guilt of a world which claims of itself the center of existence and refuses to believe in Christ - the "Babel" mentality. The Spirit will condemn this rebellion before God and will convict the inner conscience of the rebel.

v10. The Holy Spirit will also expose the world's paltry sense of justice, for Jesus will stand approved before God's judgment-seat, yet will be condemned in the world's eyes.

v11. The Holy Spirit will also expose the coming judgment, the coming condemnation of the world. This is even a "now" reality in that Satan has been overthrown through Christ's victory on the cross.

v12-13. Jesus now moves from the Spirit's work with the world to his work with believers. As the "Spirit of truth" he will lead us into "all truth." A central task of the Spirit's ministry is to guide believers into a deeper and deeper knowledge of the truth. This truth is found in Christ, so he will expound (exegete) Christ to the believer. This he will do through the apostles and their testimony, namely the New Testament. "He will tell you what is yet to come", that is, "He will show you the whole Christian way."

v14. The Spirit's ministry is to glorify Christ - to take what is Christ's and declare it to his friends.

v15. Jesus reminds us of the unity of truth that exists between the Father, the Son and the Spirit. To reveal the Son is to reveal the Father.

Our passage for study is by no means an exposition of the Trinity, but it does give us hints as to the substance of this doctrine. It's these types of hints that forced the disciples, monotheistic Jews, to view Jesus and the Holy Spirit as divine, while at the same time retaining their monotheism.

Jesus tells his disciples in v13 that a particular role of the Spirit is to lead the disciples into an understanding of the truth. Yet, this is not just the Spirit's truth; "he will not speak on his own". The Spirit is not the originator of some new radical teaching, for when it comes to the truth, the Spirit is in harmony with the Father and the Son.

Jesus goes on to say in v14 that the ministry of the Spirit is Christocentric; he is not out to build his own empire, but rather to build with Christ; he gives glory to Christ in that the truth he teaches is just as much Christ's as his own. The Spirit's ministry is to exegete the words of Christ and this he does through prophets like Paul the apostle.

Finally, in v15, Jesus makes the point that the mutual ministry of the Spirit and the Son is not to the exclusion of the Father. There is no division in the godhead, rather what the Father has, so the Son has, so the Spirit has. When it comes to the truth business, they are one.

Of course, in the end we can never understand the truth that our God is one in three persons. Like the disciples of old, we accept this truth because the Bible teaches it. Consider how theologians explain the mysterious truth of the Trinity:

i) There is only one God, Mk.12:29.

ii) The Father is God, Jn.6:27, Matt.11:25.

iii) The Son is God, Jn.1:1, 20:28.

iv) The Holy Spirit is God, Mk.3:29, Ac.5:3-4.

v) The Father, Son and Holy Spirit are distinct, ie. they are not three terms for one person, Jn.14:16.

vi) The Father is personal, Jn.15:9.

vii) The Son is personal, Mk.14:62.

viii) The Holy Spirit is personal, Rom.8:26.

vix) The Father, Son and Holy Spirit are not separate but one, Matt.28:19

vx) The three persons coinhere Jn.1:18, 10:30, 14:10, 11.

So there we have it; our God is one God in three persons. We are driven to this truth by divine revelation, a truth few would dare claim to understand.

Discuss how this doctrine affects practical matters such as prayer.