"I came to cast fire upon the earth"

Scripture: Luke 12:49-53
Jesus shocked his disciples when he declared that he would cast fire and cause division rather than peace upon the earth. What kind of fire did Jesus have in mind here? Fire in biblical times was associated with God and with his action in the world and in the lives of his people. God sometimes manifested his presence by use of fire, such as the burning bush which was not consumed when God spoke to Moses (Exodus 3:2). The image of fire was also used to symbolize God's glory (Ezekiel 1:4, 13), his protective presence (2 Kings 6:17), his holiness (Deut. 4:24), righteous judgment (Zechariah 13:9), and his wrath against sin (Isaiah 66:15-16). It is also used of the Holy Spirit (Matt. 3:11 and Acts 2:3). God's fire both purifies and cleanses, and it inspires a reverent fear of God and of his word in us.
When Jesus spoke about division he likely had in mind the prophecy of Micah: a man's enemies are the men of his own household (Micah 7:6). The essence of Christianity is loyalty to Jesus Christ.
Jesus challenges his disciples to examine who they love first and foremost. A true disciple loves God above all else and is willing to forsake all for Jesus Christ. Jesus insists that his disciples give him the loyalty which is only due to God, a loyalty which is higher than spouse or kin.