Acts 8 records a conversation with Philip and an Ethiopian eunuch.
Philip, by the leading of the Holy Spirit, encounters the Ethiopian reading Isaiah and asks, “Do you understand what you are reading?”
The Ethiopian man replies, “How can I unless someone guides me?”
Paul asks the following questions in Romans 10, “How then will they call on him in whom they have not believed? And how are they to believe in him of whom they have never heard? And how are they to hear without someone preaching? And how are they to preach unless they are sent? As it is written ‘How beautiful are the feet of those who preach the good news!’ But they have not all obeyed the gospel. For Isaiah says, ‘Lord, who has believed what he has heard from us?’ So faith comes from hearing, and hearing from the word of Christ.”
Again Paul writes, this time in Ephesians 4, “And he gave the apostles, the prophets, the evangelists, the shepherds and teachers, to equip the saints for the work of ministry, for building up the body of Christ, until we all attain to the unity of faith and of the knowledge of the Son of God to mature man hood, to the measure of the stature of the fullness of Christ, so that we may no longer be children, tossed to and fro by the waves and carried about by every wind of doctrine, by human cunning, by craftiness in deceitful schemes. Rather, speaking the truth in love, we are to grow up in every way into him who is the head, Jesus Christ, from whom the whole body, joined and held together by every joint with which it is equipped, when each part is working properly, makes the body grow so that it builds itself up in love.”
God has given people with “word gifts” to the church to announce the gospel for the salvation of his people, to announce the gospel for the equipping of his people, and to announce the gospel for the sanctification of his people. John Calvin reminds us that it is not the Word of God that needs help in these ways, but the hearers and readers. He writes, “Although the Holy Scripture contains a perfect doctrine, to which one can add nothing, since in it our Lord has meant to display infinite treasures of his wisdom, yet a person who has not much practice in is has good reason for some guidance and direction, to know what he ought to look for in it, in order not to wander hither and thither, but to hold to a sure path, that he may always be pressing toward the end to which the Holy Spirit calls him.”