In Acts 20:27, Paul told the Ephesians that he did not shrink from declaring the whole counsel of God to them. He was not selective. He was faithful to pass on all that had been delivered to him.
Today, the idea of teaching the whole counsel of God includes teaching through every book of the Bible, both Old and New Testaments, and teaching all the doctrines or teachings of the Bible without avoiding what our modern world finds offensive or uncomfortable or just irrelevant. It is that same faithfulness to pass on all that God has delivered to us in his Word.
Evangelicals are known for loving the Word and for submitting to its authority. We are less known for "teaching the whole counsel of God" because that involves a doctrinal thoroughness we fear may choke out the desire for evangelism and practical Christian living. But it also seems that we evangelicals, even though we love the Word of God, are losing our love for the words of God. We find ourselves saying that words like sanctification, justification, incarnation, predestination, or atonement are "big words" which require unappealing intellectual discussions. But these are words in our Bible!
Furthermore we often replace the vocabulary of the Bible with the vocabulary of the world. Instead of loving one another, we talk about cultivating personal relationships. Instead of avoiding fornication, we talk about abstaining from premarital sex. Instead of pursuing righteousness, we talk about promoting family values. Maybe the world can recognize these secular terms a little easier, but do they really communicate the same truths? And does anyone know what family values are?
We still have a Bible-infused culture because we are still the People of the Book. Whatever shift is going on, it is not complete. But it is real, and it seems to be gaining momentum.
To turn the tide, we need to teach the whole vocabulary of God. There is no word in the Bible that is too big. Each one can be understood. And should be understood. If we hit a word or phrase or teaching we don't get, we should aspire to learn it. We have dictionaries. We have schools. We have the Internet. They are all God-given tools. The reformation doctrine of the Perspicuity of Scripture - that Scripture is clear and can be understood - presumes that God's people care enough to use the tools he has given them to understand it.
We are wrong to think that advanced learning is all about knowing obscure things that aren't useful. It's the opposite: greater learning is needed so that we can be sure to know the things that are most important. The wise man can discern the times; the ignorant man just goes with the flow.
Let's love the Word of God as well as the words of God and get busy understanding what they are. The world is consumed with Netflix-streaming iPads: let's be consumed with God's Word, believing that it will enable us to live as a testimony of God's grace and love to those around us.