In Paul's farewell speech to the Ephesian church elders, he says, “For I did not shrink from declaring to you the whole counsel of God” (Acts 20:27, ESV). Other versions note that Paul did not hesitate to proclaim to them the whole will of God (NIV), or the whole purpose of God (NAS).
In June 2001, John MacArthur accomplished something that is extremely rare in Christendom. He finished preaching through the entire New Testament (NT), verse by verse. To his church's knowledge, this had not been done in over a hundred years or more. The one person that comes to mind is John Gill, who preached through both the OT and NT in the 1700s. Martyn Lloyd-Jones (minister of Westminster Chapel in London for almost 30 years) took more than 12 years (1955-1968) to preach verse by verse through the book of Romans. These are feats that every pastor-preacher should seek to esteem, but is challenging to ever emulate.
What does it mean to declare or proclaim the whole counsel of God? Paul roughly spent two and a half years with the Ephesian church, and it is unlikely that he managed to preach through every verse of the Old Testament (OT), line by line, with full explanation —he just simply did not have the time. D. A. Carson puts it this way, “What he must mean is that he taught the burden of the whole of God’s revelation, the balance of things, leaving nothing out that was of primary importance, never ducking the hard bits, helping believers to grasp the whole counsel of God that they themselves would become better equipped to read their Bibles intelligently, comprehensively” (Preach the Word, Ryken and Wilson, 2007).
He goes on to list key areas that encompasses this, including God’s purposes in redemptive history (truth, God), unpacking of human origin, fall, redemption and destiny (worldview, Saviour), the conduct expected of God's people (commandments, wisdom), and the pledges of transforming power both in this life and the life to come (promises, hope).
Indeed, if we hold to the Bible as truly the Word of God, this is something we need to be conscious of as Christ’s disciples, whether we are the ones preaching/teaching or studying/reading His Word. Paul reminds us in 2 Tim. to be workmen who handle God’s word correctly (2:15) as all Scripture is God-breathed and useful to thoroughly equip us for His work (3:16, 17).
Paul ends in Acts 20 by reiterating his mission in life to testify to the gospel of God’s grace (v. 24) and entrusts the Ephesian church into God’s hands and His word (v. 32). May we as a church be faithful in the preaching and study of God’s Word, that we may grow to know Christ and make Him known, for God's kingdom and glory alone.