This post was first published in July, 2016. —ed.
Most of the modern discussion about the Holy Spirit focuses on His supposedly ongoing miraculous and revelatory ministries. But despite what the charismatic church would have us believe, the Spirit is not revealing new truth and prophecies to God’s people today. Nor is He is deploying miraculous power at the whim of televangelist faith healers and prosperity preachers.
Instead, the Holy Spirit’s work always centers on the Word of God. Over the last several days we’ve focused on His role in the inspiration of Scripture. But His work did not end with the closing of the biblical canon—today He works through His Word in the lives of His people.
The Spirit Illuminates
Divine revelation would be useless to us if we were not able to comprehend it. That is why the Holy Spirit enlightens the minds of believers, so they are able to understand the truths of Scripture and submit to its teachings. The apostle Paul explained the Spirit’s ministry of illumination in 1 Corinthians 2:14-16. There he wrote,
But a natural man does not accept the things of the Spirit of God, for they are foolishness to him; and he cannot understand them, because they are spiritually appraised. But he who is spiritual appraises all things, yet he himself is appraised by no one. For “who has known the mind of the Lord, that he will instruct Him?” But we have the mind of Christ.
Through the illumination of the Word, the Holy Spirit enables believers to discern divine truth. (cf. Psalm 119:18)—spiritual realities that the unconverted are unable to truly comprehend.
The sobering reality is that it is possible to be familiar with the Bible and still fail to understand it. The religious leaders of Jesus’ day were Old Testament scholars, yet they completely missed the point of the Scriptures (John 5:37-39). As Christ asked Nicodemus, exposing the latter’s ignorance about the basic tenets of the gospel, “Are you the teacher of Israel and do not understand these things?” (John 3:10). Devoid of the Holy Spirit, unbelievers operate only in the realm of the natural man. To them, the wisdom of God seems foolish. Even after Jesus was raised from the dead, the Pharisees and Sadducees still refused to believe (Matthew 28:12-15). Stephen confronted them with these words: “You men who are stiff-necked and uncircumcised in heart and ears are always resisting the Holy Spirit; you are doing just as your fathers did” (Acts 7:51; cf. Hebrews 10:29).
The truth is that no sinner can believe and embrace the Scriptures without the Holy Spirit’s divine enabling. As Martin Luther observed,
In spiritual and divine things, which pertain to salvation of the soul, man is like a pillar of salt, like Lot’s wife, yea, like a log and a stone, like a lifeless statue, which uses neither eyes nor mouth neither sense nor heart. . . . All teaching and preaching is lost upon him, until he is enlightened, converted, and regenerated by the Holy Ghost. 
Until the Holy Spirit intervenes in the unbeliever’s heart, the sinner will continue to reject the truth of the gospel. Anyone can memorize facts, listen to sermons, and gain some level of intellectual understanding about the basic points of biblical doctrine. But devoid of the Spirit’s power, God’s Word will never penetrate the sinful soul.
Believers, on the other hand, have been made alive by the Spirit of God, who now indwells them. Thus Christians have a resident Truth Teacher who enlightens their understanding of the Word—enabling them to know and submit to the truth of Scripture (cf. 1 John 2:27). Though the Spirit’s work of inspiration applied only to the human authors of Scripture, His ministry of illumination is given to all believers. Inspiration has given us the message inscribed on the pages of Scripture. Illumination inscribes that message on our hearts, enabling us to understand what it means, as we rely on the Spirit of God to shine the light of truth brightly in our minds (cf. 2 Corinthians 4:6).
As Charles Spurgeon explained, “If you do not understand a book by a departed writer you are unable to ask him his meaning, but the Spirit, who inspired Holy Scripture, lives forever, and He delights to open the Word to those who see His instruction.”  It is a glorious ministry of the Holy Spirit that He opens the minds of His saints to understand the Scriptures (cf. Luke 24:45) so that we can know and obey His Word.
Of course, the doctrine of illumination does not mean that believers can unlock every theological secret (Deuteronomy 29:29), or that we do not need godly teachers (Ephesians 4:11-12). It also does not preclude us from disciplining ourselves for the purpose of godliness (1 Timothy 4:8) or from doing the hard work of careful Bible study (2 Timothy 2:15). Yet we can approach our study of God’s Word with joy and eagerness—knowing that as we investigate the Scriptures with prayerfulness and diligence, the Holy Spirit will illuminate our hearts to comprehend, embrace, and apply the truths we are studying.
Through His ministry of inspiration, the Holy Spirit has given us the Word of God. And through His ministry of illumination, He has opened our eyes to understand and submit to biblical truth. Yet, He does not stop there.
The Spirit Empowers
In perfect concert with His ministry of illumination, the Holy Spirit empowers His Word so that as it goes forth, it convicts the hearts of unbelievers and sanctifies the hearts of the redeemed.
In evangelism, the Holy Spirit energizes the proclamation of the biblical gospel (1 Peter 1:12), using the preaching of His Word to pierce the heart and convict the sinner (cf. Romans 10:14). As Paul told the Thessalonians, “For our gospel did not come to you in word only, but also in power and in the Holy Spirit and with full conviction” (1 Thessalonians 1:5). Elsewhere, he explained to the believers at Corinth, “And my message and my preaching were not in persuasive words of wisdom, but in demonstration of the Spirit and of power, so that your faith would not rest on the wisdom of men, but on the power of God” (1 Corinthians 2:4-5). If the Spirit did not empower the proclamation of His Word, no one would ever respond in saving faith. Charles Spurgeon vividly illustrated that point with these words:
Unless the Holy Ghost blesses the Word, we who preach the gospel are of all men most miserable, for we have attempted a task that is impossible. We have entered on a sphere where nothing but the supernatural will ever avail. If the Holy Spirit does not renew the hearts of our hearers, we cannot do it. If the Holy Ghost does not regenerate them, we cannot. If He does not send the truth home into their souls, we might as well speak into the ear of a corpse. 
The Holy Spirit is the omnipotent force behind the Lord’s promise in Isaiah 55:11—“So will My word be which goes forth from My mouth; it will not return to Me empty, without accomplishing what I desire, and without succeeding in the matter for which I sent it.” Without His divine empowerment, preaching the gospel would be nothing more than dead letters falling upon dead hearts. But through the Spirit’s power, the Word of God is “living and active and sharper than any two-edged sword, and piercing as far as the division of soul and spirit, of both joints and marrow, and able to judge the thoughts and intentions of the heart” (Hebrews 4:12).
Apart from the Holy Spirit, the most eloquent sermon is nothing but hot air, empty noise, and lifeless oratory; but when accompanied by the almighty Spirit of God, even the simplest message slices through calloused hearts of unbelief and transforms lives.
The apostle Paul similarly described the Word of God as “the sword of the Spirit” in Ephesians 6:17. In that context, Scripture is depicted as a spirit-empowered weapon that believers ought to use in their battle against sin and temptation (cf. Matthew 4:4, 7, 10). The Word of God is not only the divinely energized means by which sinners are regenerated (cf. Ephesians 5:26; Titus 3:5; James 1:18), but it is also the means by which believers resist sin and grow in holiness. As Jesus prayed in John 17:17, “Sanctify them in the truth; Your word is truth.” In 2 Timothy 3:16-17, Paul describes the sanctifying effects of God’s inspired Word—that the Scriptures are sufficient to fully equip believers for spiritual maturity.
In 1 Peter 2:1-3, Peter made a similar point:
Therefore, putting aside all malice and all deceit and hypocrisy and envy and all slander, like newborn babies, long for the pure milk of the word, so that by it you may grow in respect to salvation, if you have tasted the kindness of the Lord.
Those who have tasted of God’s grace in redemption continue to grow in sanctification through the internalization of His Word. True believers are marked by a hunger for the Scriptures, delighting in God’s Word with the intensity with which a baby craves milk (cf. Job 23:12; Psalm 119). In all of this, we are being conformed into the image of Christ—a ministry that the Spirit accomplishes by exposing our hearts to biblical revelation about the Savior (2 Corinthians 3:18). He makes it possible for “the Word of Christ [to] richly dwell within you” (Colossians 3:16), a phrase that parallels Paul’s command to “be filled with the Spirit” (Ephesians 5:18), so that the fruit of a transformed life is seen in the way we express our love to God and to others (cf. Ephesians 5:19-6:9; Colossians 3:17-4:1).
The Bible is a living book because the living Spirit of God energizes and empowers it. The Word convicts us, instructs us, equips us, strengthens us, protects us, and enables us to grow. Or more accurately, the Holy Spirit does all those things as He activates the truth of Scripture in our hearts.
As believers, we honor the Sprit when we honor the Scriptures—studying them diligently, applying them carefully, arming our minds with their precepts, and embracing their teaching with all our hearts. The Spirit has given us the Word. He has opened our eyes to understand its vast riches. And He empowers its truth in our lives as He conforms us into the image of our Savior.
Used with permission from John MacArthur.