What, according to Jesus, is the primary purpose and objective of sending the Holy Spirit at Pentecost?
If we restrict ourselves only to passages in which Jesus explicitly addresses the event that was about to take place at Pentecost, we then need to pay attention to Luke 24:46-49 and Acts 1:4-8:
46 and said to them, “Thus it is written, that the Christ should suffer and on the third day rise from the dead, 47 and that repentance for the forgiveness of sins should be proclaimed in his name to all nations, beginning from Jerusalem. 48 You are witnesses of these things. 49 And behold, I am sending the promise of my Father upon you. But stay in the city until you are clothed with power from on high.” [Luke 24:46-48, ESV]
4 And while staying with them he ordered them not to depart from Jerusalem, but to wait for the promise of the Father, which, he said, “you heard from me; 5 for John baptized with water, but you will be baptized with the Holy Spirit not many days from now.”
6 So when they had come together, they asked him, “Lord, will you at this time restore the kingdom to Israel?” 7 He said to them, “It is not for you to know times or seasons that the Father has fixed by his own authority. 8 But you will receive power when the Holy Spirit has come upon you, and you will be my witnesses in Jerusalem and in all Judea and Samaria, and to the end of the earth.” [Acts 1:4-8, ESV]
Notice that in both passages Jesus is stressing two key concepts: power (from on high) and witnessing to the rest of the world (i.e. preaching the gospel). So, based on Jesus' own words, the primary purpose of the Holy Spirit is to empower believers in order to be effective witnesses of Christ to the nations. In other words, if a Christian wants to be an effective witness of Jesus and a truthful representative of the kingdom of God here on earth, they need this power.
This naturally leads us to ask the question: what exactly does it mean to receive power from on high? Simply put, it means that Christians would be enabled by this power to do things for the kingdom of God that otherwise they wouldn't.
At Pentecost, this power manifested in two ways:
- the disciples were given the supernatural ability to speak in unknown foreign languages as a sign for unbelievers (Acts 2:1-13)
- Peter was given the ability to preach the gospel to the astonished Jewish multitude with boldness and effectiveness, winning over 3000 souls on that single occasion (Acts 2:14-41).
Of course, those were specific manifestations of the Holy Spirit at Pentecost, and they are certainly good illustrative examples of what the Spirit of God is capable of, through willing and cooperative vessels. That said, we shouldn't consider these events as prescriptive (all Christians should replicate this) or exhaustive (this is all there is to the Holy Spirit). The rest of Scripture shows us there is plenty more to the Spirit of God than what transpired at Pentecost.
What are other functions of the Holy Spirit in a Christian's life?
- To enable Christians to do the same works that Jesus did:
38 how God anointed Jesus of Nazareth with the Holy Spirit and with power. He went about doing good and healing all who were oppressed by the devil, for God was with him. [Acts 10:38, ESV]
12 “Truly, truly, I say to you, whoever believes in me will also do the works that I do; and greater works than these will he do, because I am going to the Father. 13 Whatever you ask in my name, this I will do, that the Father may be glorified in the Son. 14 If you ask me anything in my name, I will do it. [John 14:12, ESV]
- To be a Helper for the Christian throughout their entire life:
15 “If you love me, you will keep my commandments. 16 And I will ask the Father, and he will give you another Helper, to be with you forever, 17 even the Spirit of truth, whom the world cannot receive, because it neither sees him nor knows him. You know him, for he dwells with you and will be in you. [John 14:15-17, ESV]
- To enable Christians to preach the gospel with boldness:
29 And now, Lord, look upon their threats and grant to your servants to continue to speak your word with all boldness, 30 while you stretch out your hand to heal, and signs and wonders are performed through the name of your holy servant Jesus.” 31 And when they had prayed, the place in which they were gathered together was shaken, and they were all filled with the Holy Spirit and continued to speak the word of God with boldness. [Acts 4:29-31, ESV]
- To produce fruit (aka sanctification):
22 But the fruit of the Spirit is love, joy, peace, patience, kindness, goodness, faithfulness, 23 gentleness, self-control; against such things there is no law. 24 And those who belong to Christ Jesus have crucified the flesh with its passions and desires. 25 If we live by the Spirit, let us also keep in step with the Spirit. 26 Let us not become conceited, provoking one another, envying one another. [Galatians 5:22-26, ESV]
2 according to the foreknowledge of God the Father, in the sanctification of the Spirit, for obedience to Jesus Christ and for sprinkling with his blood: May grace and peace be multiplied to you. [1 Peter 1:2, ESV]
13 But we ought always to give thanks to God for you, brothers beloved by the Lord, because God chose you as the firstfruits to be saved, through sanctification by the Spirit and belief in the truth. 14 To this he called you through our gospel, so that you may obtain the glory of our Lord Jesus Christ. [2 Thessalonians 2:13-14, ESV]
- To give spiritual gifts for the common good:
4 Now there are varieties of gifts, but the same Spirit; 5 and there are varieties of service, but the same Lord; 6 and there are varieties of activities, but it is the same God who empowers them all in everyone. 7 To each is given the manifestation of the Spirit for the common good. 8 For to one is given through the Spirit the utterance of wisdom, and to another the utterance of knowledge according to the same Spirit, 9 to another faith by the same Spirit, to another gifts of healing by the one Spirit, 10 to another the working of miracles, to another prophecy, to another the ability to distinguish between spirits, to another various kinds of tongues, to another the interpretation of tongues. 11 All these are empowered by one and the same Spirit, who apportions to each one individually as he wills. [1 Corinthians 12:4-11, ESV]
Answers to specific sub-questions:
Is the primary objective of the Holy Spirit to imbue believers with the miraculous gifts of speaking in tongues, or of healing, or of prophecy?
I wouldn't say that's the primary objective. It definitely is one of the several functions of the Holy Spirit, and therefore it's useful, important and it is there for a reason. But if I had to single out one specific function of the Holy Spirit which I consider to be the most important, that would be the fruit of love. Love is the first one in the list of fruits of the Spirit according to Paul in Galatians 5:16-26. Also, we all know what Jesus' response was when he was asked to point out the most important commandment in God's law. Paraphrasing him, he basically said that everything boils down to love: love for God and love for our neighbors. I think 1 Cor 13 is the chapter that best explains this point:
If I speak in the tongues of men and of angels, but have not love, I
am a noisy gong or a clanging cymbal. 2 And if I have prophetic
powers, and understand all mysteries and all knowledge, and if I have
all faith, so as to remove mountains, but have not love, I am nothing.
3 If I give away all I have, and if I deliver up my body to be
burned, but have not love, I gain nothing.
4 Love is patient and kind; love does not envy or boast; it is not
arrogant 5 or rude. It does not insist on its own way; it is not
irritable or resentful; 6 it does not rejoice at wrongdoing, but
rejoices with the truth. 7 Love bears all things, believes all things,
hopes all things, endures all things.
8 Love never ends. As for prophecies, they will pass away; as for
tongues, they will cease; as for knowledge, it will pass away. 9 For
we know in part and we prophesy in part, 10 but when the perfect
comes, the partial will pass away. 11 When I was a child, I spoke like
a child, I thought like a child, I reasoned like a child. When I
became a man, I gave up childish ways. 12 For now we see in a mirror
dimly, but then face to face. Now I know in part; then I shall know
fully, even as I have been fully known.
13 So now faith, hope, and love abide, these three; but the greatest
of these is love.
Is the manifestation of those gifts of the Spirit in the believer proof that they are somehow superior to those who have never experienced such miraculous gifts?
I know no biblical basis to answer this question with a "yes". On the contrary, I see every reason to think that someone who has been perfected in the fruit of love is in a much more admirable position than someone who has many spiritual gifts but is lacking in love (see 1 Cor 13 quoted above). That said, love and spiritual gifts are not mutually exclusive. In fact, Jesus had both, and I see no reason why a Christian would not want to enjoy the best of both worlds, following Jesus' example. So the optimal situation for a Christian would be (1) to have been perfected in love and (2) to be anointed by God's Spirit in order to have gifts and be a powerful witness for Christ.