It might surprise you that there is no passage in the Bible that says “Speak where the Bible speaks and be silent where the Bible is silent.” This is a slogan that has derived from a quote from Thomas Campbell.
There are however several passages that teach this in principle. Four of these passages explicitly say not to add or detract from what has been written.
In Deut 4:2 it says, “You shall not add to the word that I command you, nor take from it, that you may keep the commandments of the Lord your God that I command you.”
Again, in Deut 12:32 it says, “Everything that I command you, you shall be careful to do. You shall not add to it or take from it.”
Then in Prov 30:6 it is written, “Do not add to his words, lest he rebuke you and you be found a liar.”
Finally, in Rev 22:18-19 it warns, I warn everyone who hears the words of the prophecy of this book: if anyone adds to them, God will add to him the plagues described in this book, and if anyone takes away from the words of the book of this prophecy, God will take away his share in the tree of life and in the holy city, which are described in this book.
These passages give two clear, explicit commands: Do not add to the commandments and do not take away from the commandments.
Another passage that speaks to this discussion is Deut 29:29 which says, “The secret things belong to the Lord our God, but the things that are revealed belong to us and to our children forever, that we may do all the words of this law.” The indication seems to be that anything not revealed by God is for him. He has revealed his will for us, and that is what we should be concerned with.
Lastly, Deut 18:20 needs to be considered. It says, “But the prophet who presumes to speak a word in my name that I have not commanded him to speak, or who speaks in the name of other gods, that same prophet shall die.’”
Paul also had a few things to say about respecting the authority of the word of God. In 1 Cor 4:6, he wrote, “I have applied all these things to myself and Apollos for your benefit, brothers, that you may learn by us not to go beyond what is written, that none of you may be puffed up in favor of one against another.” He warns the Corinthians to not “go beyond what is written.” Paul also gave warnings, to those to whom he ministered, not to accept revelations or anything that is different than what they had received. He wrote to the Galatians, “I am astonished that you are so quickly deserting him who called you in the grace of Christ and are turning to a different gospel— not that there is another one, but there are some who trouble you and want to distort the gospel of Christ. But even if we or an angel from heaven should preach to you a gospel contrary to the one we preached to you, let him be accursed. As we have said before, so now I say again: If anyone is preaching to you a gospel contrary to the one you received, let him be accursed” (Gal 1:6-9). Paul seems to put an emphasis on Christians focusing on what has been delivered, rather than what has not been delivered.
John also wrote that Christians should not go beyond the word of God. In 2 John 9-10 he wrote, “Everyone who goes on ahead and does not abide in the teaching of Christ, does not have God. Whoever abides in the teaching has both the Father and the Son. If anyone comes to you and does not bring this teaching, do not receive him into your house or give him any greeting.”
Therefore, when God speaks for or against something, we must also speak. Yet when God is silent about something, we must also remain silent or we risk saying something that He did not.God’s word is powerful. Let’s rely on His word rather than our own opinions. Only his words contain eternal and abundant life.