I like how Misses Ellen Gould White put it:
The truth and the glory of God are inseparable; it is impossible for us, with the Bible within our reach, to honor God by erroneous opinions. Many claim that it matters not what one believes, if his life is only right. But the life is molded by the faith. If light and truth is within our reach, and we neglect to improve the privilege of hearing and seeing it, we virtually reject it; we are choosing darkness rather than light.
"There is a way that seemeth right unto a man, but the end thereof are the ways of death." Proverbs 16:25. Ignorance is no excuse for error or sin, when there is every opportunity to know the will of God. A man is traveling and comes to a place where there are several roads and a guideboard indicating where each one leads. If he disregards the guideboard, and takes whichever road seems to him to be right, he may be ever so sincere, but will in all probability find himself on the wrong road.
God has given us His word that we may become acquainted with its teachings and know for ourselves what He requires of us. When the lawyer came to Jesus with the inquiry, "What shall I do to inherit eternal life?" the Saviour referred him to the Scriptures, saying: "What is written in the law? how readest thou?" Ignorance will not excuse young or old, nor release them from the punishment due for the transgression of God's law; because there is in their hands a faithful presentation of that law and of its principles and claims. It is not enough to have good intentions; it is not enough to do what a man thinks is right or what the minister tells him is right. His soul's salvation is at stake, and he should search the Scriptures for himself. However strong may be his convictions, however confident he may be that the minister knows what is truth, this is not his foundation. He has a chart pointing out every waymark on the heavenward journey, and he ought not to guess at anything.
It is the first and highest duty of every rational being to learn from the Scriptures what is truth, and then to walk in the light and encourage others to follow his example. We should day by day study the Bible diligently, weighing every thought and comparing scripture with scripture. With divine help we are to form our opinions for ourselves as we are to answer for ourselves before God.
The truths most plainly revealed in the Bible have been involved in doubt and darkness by learned men, who, with a pretense of great wisdom, teach that the Scriptures have a mystical, a secret, spiritual meaning not apparent in the language employed. These men are false teachers. It was to such a class that Jesus declared: "Ye know not the Scriptures, neither the power of God." Mark 12:24. The language of the Bible should be explained according to its obvious meaning, unless a symbol or figure is employed. Christ has given the promise: "If any man will do His will, he shall know of the doctrine." John 7:17. If men would but take the Bible as it reads, if there were no false teachers to mislead and confuse their minds, a work would be accomplished that would make angels glad and that would bring into the fold of Christ thousands upon thousands who are now wandering in error. (The Great Controversy, p. 598) (Ellen Gould White, The Great Controversy, pp. 597, 598)
Faith in a lie will not have a sanctifying influence upon the life or character. No error is truth, or can be made truth by repetition, or by faith in it. Sincerity will never save a soul from the consequences of believing an error. Without sincerity there is no true religion, but sincerity in a false religion will never save a man. I may be perfectly sincere in following a wrong road, but that will not make it the right road, or bring me to the place I wished to reach. The Lord does not want us to have a blind credulity, and call that the faith that sanctifies. The truth is the principle that sanctifies, and therefore it becomes us to know what is truth. We must compare spiritual things with spiritual. We must prove all things, but hold fast only that which is good, that which bears the divine credentials, which lays before us the true motives and principles which should prompt us to action.Letter 12, 1890. (Ellen Gould White, 2 Selected Messages, p. 56)
Some who are unacquainted with the Bible think that what the ministers tell them must be true. They do not, like the noble Bereans, search the Scriptures for themselves; but they accept the statements of those who have studied the word of God, not to learn the truth, but to sustain false doctrines, to justify their own theories. Many times these false theories are a jumble of inconsistencies; and if men would use their reason, and take the Bible as it reads, they would see the absurdity of their positions. The plain "Thus saith the Lord," would dispel their errors, as the mist is dispelled by the glories of the rising sun.
As Protestants, the Bible, and the Bible alone, is the foundation of our faith; but by many "the Fathers" are quoted as authority. They do not come as humble learners in the school of Christ, saying, "Lord, what I know not, teach me. 'Open thou mine eyes, that I may behold wondrous things out of thy law.'"
Says the wise man: "Let us hear the conclusion of the whole matter: Fear God, and keep his commandments; for this is the whole duty of man. For God shall bring every work into judgment, with every secret thing, whether it be good, or whether it be evil." Men may close their eyes to the plainest truths in the word of God, they may trample his law under their feet; but the law, instituted in the beginning, proclaimed from Sinai, and engraven on tables of stone, will judge them in the last day. (Ellen Gould White, The Signs of the Times, August 5, 1886 par 13-15)