Since the fall of man in Eden, the tempter has been most successful in reaching men when he is able to deceive them into thinking that his voice is the voice of God. "Men must be in close connection with God, or the enemy will interpose himself between them and God, that they will take his suggestions as the voice of God." 1888 Messages, 939
In order to avoid being shaken out of with any device of our adversary who is much wiser than we are, we must know with certainty the voice of God and then obey it.
Many times in the book of Genesis God spoke to individuals but in Exodus, He speaks not only to individuals but to the entire world from Mount Sinai in giving His Law. "The earth shook, the heavens also dropped at the presence of God: even Sinai itself was moved at the presence of God, the God of Israel. Psalm 68:8. Amid the most terrific convulsions of nature the voice of God, like a trumpet, was heard from the cloud. The mountain was shaken from base to summit and the hosts of Israel, pale and trembling with terror, lay upon their faces upon the earth. He whose voice then shook the earth has declared, ‘Yet once more I shake not the earth only, but also heaven.’ " Patriarchs and Prophets, 340. Concerning what He spoke, He declares "My covenant I will not break, nor alter the word that has gone out of My lips." (The Ten Commandments are called is covenant. See Deuteronomy 4:13; 5:22.)
Any voice with any message can be compared to the Law of God. God’s voice will never contradict His Law and any voice that does contradict His Law is not His voice no matter what claim may be made. It is this stabilizing knowledge that will be one of the main factors that will keep the elect from being deceived in the times of trouble just ahead. (See The Great Controversy, 622-626.) There are mysteries in the Bible that the wisest minds cannot fathom, but this is not true concerning the law of God. "There is no mystery in the law of God. The feeblest intellect can grasp these rules to regulate after the Divine Mode." Review and Herald, September 14, 1886
But God’s voice is heard not only in the Ten Commandments. "Do we receive the testimony of the Scriptures as the voice of God? Through the Scriptures, the voice of God comes to us as veritably as it came to Israel when He spoke on Sinai in the audience of all the people. How many of us regard it in this light? If we did regard it thus, what a change would be seen in our daily words and actions. With what reverence and awe would we search the Word of God to know the truth, the medium through which the souls sanctification is accomplished." Signs of the Times, April 6, 1891. If we could fully realize the truth of this statements, how the Holy Bible would be prized. It would be considered the greatest of any material possession that could be acquired in this world. It would be realized that this Book allows us to have an audience with our Maker Who holds the destiny of every living thing in His hands and has in this Book graciously shown to us how to live so as to obtain life’s best results.
"The Lord has uttered His voice in His Holy Word. Those blessed pages are full of instruction and life, harmonious with truth. They are a perfect rule of conduct. Instructions are given, principles are laid down, which apply to every circumstance in life, even though some particular case may not be stated. Nothing is left unrevealed which is essential to a complete system of faith and a correct line of practice. Every duty that God requires at our hands is made plain…None will err from the right path who meekly and honestly take the Bible as their guide, making it the man of their counsel." Our High Calling, 36
There are other ways in which the Lord speaks to the children of men, but it is basic to understand that the voice of God will never contradict the Scriptures, especially the Ten Commandments. If the voice of any person, organization, or group of persons, no matter how many miracles are performed or how many signs and wonders, are worked proclaims a message contrary to the established and certain vice which has stood the test of many centuries of criticism and abuse and has given unmistakable evidence of its source, the we may know that, however pleasing, this voice is neither the voice of God nor speaking for God. (See Matthew 7:21-23.)