The best way for a Christian to be is on fire for Jesus and have a strong zeal for God, it is the way Jesus wants us to be:
“Who maketh his angels spirits; his ministers a flaming fire:” Psalms 104:4
Our fire for God should be burning at all times, we should never be afraid to spread the gospel of Jesus. But this fire always needs to be contained within the Holy Ghost as we walk in the Spirit and not the flesh. It is easy at times especially for newer believers to get so excited that we yield to the flesh a bit and get caught up in non salvational issues and worldly arguments or preach something that we really have not learned 100% ourselves.
“For I bear them record that they have a zeal of God, but not according to knowledge.” Romans 10:2
Sometimes newer Christians with a big zeal feel the desire to be leaders and teachers when they still have a lot to learn. It is important that we stay humble and find a Godly Holy Ghost filled church and pastor to learn and serve in as much as we can before the Holy Ghost directs us to be leaders and teachers for the Bible teaches we will be held accountable.
“My brethren, be not many masters, knowing that we shall receive the greater condemnation.” James 3:1
When James and John saw that the Samaritans rejected Jesus their fire inside them was kindled with good intentions but it was not fully contained in the Holy Ghost. They wanted to call fire down on the Samaritans, they were yielding partially to their flesh and Jesus rebuked them:
“54 And when his disciples James and John saw this, they said, Lord, wilt thou that we command fire to come down from heaven, and consume them, even as Elias did? 55 But he turned, and rebuked them, and said, Ye know not what manner of spirit ye are of.” Luke 9:54-55
Now raining down fire from Heaven is not a bad thing, but it is ultimately God’s decision made with perfect justice like He did to the sodomites:
“Then the LORD rained upon Sodom and upon Gomorrah brimstone and fire from the LORD out of heaven;” Genesis 19:24
A fire gives light, warmth, cooks, it has many uses for life as does our fire we have for the Lord. A campfire started in California for the correct reasons and not contained properly can quickly become a wildfire and destroy millions of acres of land and property. We must always keep in mind that our fire can burn as strong as we want it to as long as it is contained in the Holy Ghost where it will give light to a dark and dying world. We would never want our zeal and fire for the Lord to become an out of control wildfire which could actually cause destruction when we are yielding to the flesh and not the Spirit of God.