[The Christian concept of the Trinity is difficult to understand.
Fundamental Christianity claims that there is but one God, yet this God is three distinct “people”. It also claims that each “person” has a certain role, even though they are all intrinsically equal since they are all God. One person has authority over the two other people, one person is referred to as the “Son” of the person who has authority, and the last person is the referred to as the “Spirit” of God. As you could clearly see, this is a very complex and paradoxical concept of theology.
This article is not about the Trinity in general, but about this last “person” whom we call the “Holy Spirit (or Holy Ghost)”. Since the Bible describes God the Father and Jesus Christ a lot more than it describes the Holy Spirit (the “Spirit of God” is mentioned throughout the Bible and He’s given a few more roles in the New Testament, but not too much information is given compared to the other two), writing about the Spirit is a bit of a challenge because I don’t want to commit heresy or step on anyone’s “theological toes” (although I doubt that either will happen if someone disagrees with me, the perfectionist in me sometimes likes to take unnecessary precaution).
Regardless, the very fact that He is part of the Trinity makes Him as important as the Father and Son, and that makes Him worth discussing, even if we get it wrong]
If I were a king who sent out my beloved heir to a foreign country, and I wanted him to experience my guidance and wisdom during the trip, how might I go about doing this? I would send an extremely close and trusted advisor along with him. This advisor would teach the heir everything he needs to know in order to conduct business in this country and prepare it for his father so that when the king finally arrives, he could rule with ease.
This is similar to how God the Father helps the Church on Earth: He sends His Spirit in order to teach us and to give us the resources that we need to expand His Kingdom on Earth. This analogy, however, is imperfect, since the Spirit is “divine” and cannot simply be compared to a human. For instance, the Holy Spirit has more of an intimate relationship with the Father than any human (so much that we also call Him “God”), and He acts as the Father's "seal" on His people (2 Corinthians 5:5), meaning that they will always belong to Him. Therefore, the Spirit deserves as much respect as the Father and Son, and He can greatly enrich our lives if we allow Him to guide us; this relates to what Isa spoke about.
“Spirit-led lives bring influence and strength” was the name of Isa’s sermon, where she talked about how living a life full of the Spirit can bring us purpose, and about the power it provides. She also described the Holy Spirit as a “creator” and as someone who is currently “molding” the Church. The Spirit can also give us influence and strength (in humility) wherever we go, and He supplies us with gifts so that we can help the Church thrive and grow. Bottom line, the Holy Spirit has a very important role when it comes to God’s Earthly ministry.
Since He’s not as popular as God the Father or Jesus, we usually take the Spirit for granted. This shouldn’t be, since He is just as important as the other two, especially considering the fact that he is actively involved in the Church. He’s also currently living in every believer (Romans 8:7), and if you allow Him, He gradually transforms your soul with the goal of making it holy (Galatians 5:22-23 lists the “fruits” of the Spirit which will cultivate within the believer).
Also, as Isa mentioned, the Spirit gives us gifts in order to better serve God and the Church (1 Corinthians 12:4-6). Since these gifts are spiritual, and not natural, we must be good stewards of God and use them as best as we can. We must cultivate these gifts, not only because they were sent from above and we should respect “heavenly” things, but because they were given to us for the sole purpose of building up the Church; these gifts are not for our own enjoyment or personal use, but for His glory. So, if you believe the Spirit has gifted you in a certain area (or several areas), consider it a “calling” and don’t hesitate to bless the Church with it.
In John 14:26, Jesus labels the Holy Spirit as the “Helper” (in the ESV translation) who “will teach us all things and bring to our remembrance all that Jesus has said to us”. In other words, He is a “replacement” of Jesus, who is currently in Heaven, and He fulfills the role that Jesus would have if He were with us on Earth (In John 16:7, Jesus claims that it is to our “advantage” that He leave, so that the Spirit will come to us). Some ways in which the Spirit emulates Jesus are by teaching, comforting, and counseling; given these facts, being indwelled with the Spirit not only results in a relationship with the Father, but also with Jesus Christ, and this relationship will never end. Hence, when the Spirit lives in us, we will always “walk with Jesus”.
(This, of course, doesn’t mean we can’t do wrong by the Spirit, since He can be “quenched” (1 Thessalonians 5:19) and “grieved” (Ephesians 4:30) by sin; therefore, we must avoid sin at all costs if we want Him to work in our lives as best He can)
There are many more roles of the Spirit which are not listed here (some include helping us in prayer (Romans 8:26) and convicting the world concerning sin, righteousness, and judgment (John 16:8)); I also have little doubt that even the Bible can’t describe everything He does on Earth. However, what the “Advisor” does and how He operates is not as important as the reason He was sent by the “King”: to send a substitute of His “Primary Heir” which His other “heirs” can access here on Earth, to transform their souls into ones similar to that of which belongs to the “Primary Heir”, to help them build His Kingdom on Earth by giving them gifts and resources, and to establish a permanent "seal" on them, proving to them that they belong to the King.
Thus, He might be the “Third Guy”, but at the end of the day, He’s still a “Guy".
[and hopefully I’m not a heretic now]