To be “on fire” is to be eager, zealous, or “burning” with enthusiasm. Sometimes we speak of “lighting a fire under” someone, by which we mean “motivating” that person or “urging” him or her to action. Related expressions used in the church include on-fire Christian (“a zealous Christian”) and on fire for the Lord (“filled with enthusiasm for God”). Such idioms are not in the Bible, but we do find examples there of people with “burning” zeal and descriptions of the Lord’s work using terms associated with “fire.”
The Old Testament counterpart of an “on-fire” Christian is a person who had zeal for the Lord and acted on it. Examples include Phinehas (Numbers 25:10–11), David (1 Samuel 13:14; 1 Kings 3:6), Elijah (1 Kings 19:10–14), Hezekiah (2 Kings 18:1–7), and Josiah (2 Kings 22–23).
John the Baptist told the crowds about the coming Messiah, “He will baptize you with the Holy Spirit and with fire” (Matthew 3:11). That prophecy was first fulfilled on the day of Pentecost after Jesus’ resurrection. The disciples were huddled together in a house, fearing persecution, when the Holy Spirit came on each in the form of “tongues of fire” (Acts 2:2–3). Instantly, their fear was replaced with supernatural boldness and zeal for the Lord. These “on-fire Christians” went out into the streets of Jerusalem and fearlessly preached the gospel to huge crowds, including the same people who had recently murdered Christ.
The result was clearly a miracle. Three thousand people came to Christ after just one sermon (Acts 2:41). These new believers, who were certainly “on fire for the Lord,” exhibited love, sacrificial giving, and service to others. Phenomenal church growth continued as the apostles continued preaching and “everyone was filled with awe at the many wonders and signs performed by the apostles” (verse 43).
The “on-fire” apostles were marked by a boldness to serve God without compromise, whatever the personal cost or danger. The Sanhedrin was astonished by “the courage of Peter and John,” who were “unschooled, ordinary men” (Acts 4:13). When arrested and ordered to stop preaching about Jesus, the apostles replied, “Judge for yourselves whether it is right in God’s sight to obey you rather than God. For we cannot help speaking about what we have seen and heard” (verses 19–20). The next time they were arrested and ordered to stop, they replied, “We must obey God rather than men!” (Acts 5:29). When they were beaten, they rejoiced for being “counted worthy of suffering disgrace for the Name” (verse 41). Such is the behavior of those who are “on fire” for the Lord.
Before His crucifixion, Jesus revealed some of the difficulties coming to His followers. Not only would Christians face opposition from the rulers, but even from their own families: “I have come to bring fire on the earth, and how I wish it were already kindled! But I have a baptism to undergo, and what constraint I am under until it is completed! Do you think I came to bring peace on earth? No, I tell you, but division. From now on there will be five in one family divided against each other, three against two and two against three. They will be divided, father against son and son against father, mother against daughter and daughter against mother, mother-in-law against daughter-in-law and daughter-in-law against mother-in-law” (Luke 12:49–53).
The opposite of an “on-fire” Christian is a lukewarm one. The wealthy, complacent believers in Laodicea were rebuked by the Lord: “I know your deeds, that you are neither cold nor hot. I wish you were either one or the other! So, because you are lukewarm—neither hot nor cold—I am about to vomit you out of my mouth” (Revelation 3:15–16). Lukewarm is the least desirable attribute for water or for spiritual commitment. Spiritually, a person who is “hot” or “on fire” for Christ can be very useful. But a person who is “lukewarm” toward Jesus possesses only tepid commitment and lives without joy, without love, and without the fire of the Spirit. “They will act religious, but they will reject the power that could make them godly” (2 Timothy 3:5, NLT).
Christians who are “on fire” for the Lord reject the safe, comfortable life in favor of accomplishing God’s will; they actively “pursue righteousness, godliness, faith, love, endurance and gentleness” (1 Timothy 6:11). They are “eager to do what is good” (Titus 2:14). Some believers today need to heed Paul’s advice: “I remind you to fan into flames the spiritual gift God gave you” (2 Timothy 1:6, NLT).