What is your one sermon? If you are a believer, you have one. If you are a believer who has been called to preach the unsearchable riches of Christ to others, then you surely have one. Your one sermon is what God has done in your life. Your one sermon is your sacred encounter. It is your divine calling. It may be the one sermon of a faithful covenant family who was used by God to bring you to Christ in the home with godly examples. Your calling to preach came as you realized the brokenness of the world, which had not had that experience. Or, it may be the sacred encounter of Christ in a prison cell and then the wrestling you had when you knew God was calling you to preach, as in the case of Charles Colson, to other prisoners, whether bound in the shackles of a penitentiary or the chains of false religion. That is your one sermon.
John Wesley was a "brand plucked from the burning" and that theme runs throughout all his messages. George Whitefield burned alive with the glory of his assurance of salvation. Can you read Whitefield and not come away with that one sermon? C.H. Spurgeon was arrested by the lay preacher who called for him to "look, look!" and to see his salvation in the Lord. He would call many others to look to God in thousands of messages, strong with that one compelling mandate, which became his one sermon.
What is your one sermon? What makes you burn alive with Christ until your messages break out in a holy conflagration of praise? That one sermon is the work of God in you, and it will be the Spirit-compelling feature of your ministry, which will cause you to preach every sermon from every text with gospel power and scriptural faithfulness. Your one sermon will be the Spirit-sent way the Word of God is preached that awakens the one sermon in another.
I, therefore, appeal to you now: Bring all of your studies to the bar of God, recalling His work in your life, His call on your life; and go to preach one sermon for the rest of your life. Others will break into spontaneous doxological combustion, too.
From The Secret Life of a Pastor and Other Intimate Letters on Pastoral Ministry (Christian Focus Pub., 2015).