Westminster Confession, Chapter 1, Paragraph 1
Of the Holy Scriptures
I. Although the light of nature, and the works of creation and providence do so far manifest the goodness, wisdom, and power of God, as to leave men unexcusable; yet are they not sufficient to give that knowledge of God, and of his will, which is necessary unto salvation. Therefore it pleased the Lord, at sundry times, and in divers manners, to reveal himself, and to declare that his will unto his church; and afterwards, for the better preserving and propagating of the truth, and for the more sure establishment and comfort of the church against the corruption of the flesh, and the malice of Satan and of the world, to commit the same wholly unto writing: which maketh the Holy Scripture to be most necessary; those former ways of God’s revealing his will unto his people being now ceased.
It is quite amazing to note that not one person has ever been brought into a saving relationship with God apart from divine communication. In past days, God spoke to his people through a bush, through prophets, and the occasional voice from heaven. Even Adam (perfect / innocent man) needed God to walk with him, talk with him, and instruct him as to the will of God. Adam did not innately know the will of God apart from being told.
Because of the writings of Scripture, God has made a way for many more people to know his will. His word has been preserved for us this day and we have the privilege to pass down the truth to our children and grand-children. The confession calls the Scriptures most necessary. The Scripture says it like this:
2 Timothy 3:15–17 and how from childhood you have been acquainted with the sacred writings, which are able to make you wise for salvation through faith in Christ Jesus. All Scripture is breathed out by God and profitable for teaching, for reproof, for correction, and for training in righteousness, that the man of God may be complete, equipped for every good work.
2 Peter 1:19–21 And we have the prophetic word more fully confirmed, to which you will do well to pay attention as to a lamp shining in a dark place, until the day dawns and the morning star rises in your hearts, knowing this first of all, that no prophecy of Scripture comes from someone’s own interpretation. For no prophecy was ever produced by the will of man, but men spoke from God as they were carried along by the Holy Spirit.