God prepared the hearts of people for His Son, Jesus Christ, to come through the preaching of John: “In those days came John the Baptist, preaching in the wilderness of Judea” (Mt. 3:1). John’s message was repentance—turning from sin and changing one’s heart and will regarding sin. Repentance is never a popular message, but it is necessary.

John fulfilled the prophecy of Isaiah 40:3 as the voice crying in the wilderness that prepared the way for the Lord. “Every valley shall be exalted, and every mountain and hill shall be made low: and the crooked shall be made straight, and the rough places plain” (Isa. 40:4). Sometimes, people interpret the Bible’s prophecies too literally. John was not a literal road construction worker.  Those who look to the Old Testament prophets as describing wars erupting in our time in certain nations and the same physical locations in the Middle East err in this overly literal approach. Matthew 3:3-4, Mark 1:3, and Luke 3:4-5 clearly show that Isaiah 40:4 was fulfilled in John’s work. The context bears out that this smoothing of the paths was repentance in the heart.

The people who heard John were to bring forth fruits worthy of repentance (Lk. 3:8). The people were told to start being merciful as evidence of their repentance (Lk. 3:10-11). The tax collectors, who were viewed as low-down places in the path, were told to exact no more tax than appointed (Lk. 3:12, 13). The rough soldiers were smoothed out in being instructed to do violence to no man (Lk. 3:14). In this way, people’s hearts were prepared for Jesus. They would be more ready to receive the words of eternal life He came to give (Jn. 6:68).

The first thing Jesus is recorded preaching in the New Testament is a similar message to John’s—repentance, “From that time Jesus began to preach, and to say, Repent: for the kingdom of heaven is at hand” (Mt. 4:17; cf. Mk. 1:15). Jesus came as king (Zech. 9:9; Mt. 21:5; Jn. 12:13; 18:36-37). The paths were smoothed for the king’s chariot. Hearts had to be smoothed to receive Jesus. Repentance is absolutely necessary if one will enter the kingdom of God. Jesus cannot be our king if we do not humble ourselves, change our hearts, and submit to His will (Mt. 7:21-23; Lk. 6:46).

Paul preached Jesus Christ to the Gentiles (Gal. 2:2; Eph. 3:8; 2 Tim. 1:11; 4:17). His preaching included repentance (Acts 17:30-31). He instructed the younger preacher Timothy: “Preach the word; be instant in season, out of season; reprove, rebuke, exhort with all longsuffering and doctrine” (2 Tim. 4:2). People need to hear the word of God. God’s word is sharper than any sword (Heb. 4:12); it can pierce their hearts and result in repentance (Acts 2:37). Preaching must not only be exhorting but must also include reproving and rebuking. The word of God is the sword of the Spirit (Eph. 6:17), convicting men of their sins (Jn. 16:8). Many self-help guides are popular today that attempt to relieve one of all guilt, but if the problem is self, then self-help cannot offer the true solution. Preaching that causes people to be sorry for their sins is desperately needed. Godly sorrow is a prerequisite to repentance (2 Cor. 7:9-11).

From John, to Jesus, to Paul, to faithful gospel preachers today: repentance has always been an essential to the preaching that converts one to Christ. We are to preach the gospel to all creation (Mk. 16:15). Repentance must be preached to all nations (Lk. 24:47).