Introduction
In Luke 12:49 we find an interesting passage, "I am come to send fire on the earth; and how I wish it were already kindled!" Jesus came to make a difference in this world--to shake the spirits, to open the fountain of redemption, to make mankind anxious for regeneration, to help us ask where we are coming from, where we are going.
Today there is a crisis of faith. Externally in our world--we see liberalism, materialism, humanism, individualism, hedonism. In the religious world we find ecumenism, soft theologies, Biblical ignorance. But the greatest failure is internal. We are failing, failing God, failing to act, failing self, failing our world.
Christianity urgently needs men and women to send fire to our world, men and women who are genuinely converted, those who see God's eternal purpose, who have a real message on their hearts, who are moved by the love of Christ, who are obedient to the heavenly call. This should describe everyone of us, but it does not. Here is our failure.
This is sometimes a failure because we are not prepared, we have not prepared ourselves. At other times it is a failure because we have failed to answer the call when we are prepared.

I. God calls.
We take for our text today, Jer. 20:9. The fire Jeremiah felt in his bones, the spiritual fire, originated with God. God's flame burns in the soul of every person called to his service. God called Jeremiah (1:5). God does not use the same procedure for all. Isaiah's call was distinct (Isa. 6). Ezekiel was called by spectacular visions (Ezek. 23). Jeremiah's call, by contrast, seems natural, usual. God's word comes to him. Jeremiah protests, as you and I often do. But God is calling Jeremiah. God is putting a fire in Jeremiah's bones.

II. A consuming call.
When fire is within us, we are consumed. Internal fire confronts the spiritual coldness in the world, but first confronts the spiritual coldness within our hearts. Psalm 39:3 says meditation started the fire. Jeremiah felt the fire. He answered the call.
God within us does not consume us, and the world questions his genuine presence within us. Fire can smolder for just so long, and it breaks forth. The cold reception of the message in our world, a message that fails to consume hearts, is explained by the cold reception of the message in the church of Christ, the very people of God. The spiritual ignorance of our world is explained by the spiritual ignorance among us.

III. A convicting call.
Jeremiah's conviction is apparent in 15:15-18. We do not know how the prophet died, but we do know he was convicted and answered the call of God even in the face of death and persecution by his countrymen. A Jewish story accepted by early Christians says Jeremiah died in Taphnes, stoned by his own people. He was undoubtedly persecuted, even imprisoned, but God's convicting call cannot be ignored.
In our heart of hearts, we have wanted to do more than we are doing in missions. I want to give more. Brother, sister, do what God is laying on your heart to do.
Only those with convictions can make a difference in our world. Salesmen must be convicted and convinced of the value of the product they offer. We have claimed the fire of God without the flame of God. The fire has just about gone out in many hearts. Faith slips, hearts sink in doubt.

IV. A continuing call.
God said, you speak what I command (1:7). With the fire of his missions burning inside him, he spoke a short sermon: 22:29. Whether God's message is a sword bring war or an offering bringing peace, God calls us to continually spread the message as we go into all the world by going into the spheres of our individual worlds.
The call is not continual for many Christians today because we have lost sight of the purpose of our existence. Our question is similar to that of the prophet in Jeremiah 20:18. To serve God is a difficult task, full of obstacles. To overcome the obstacles, the servant of God must maintain a clear vision of his mission. We have an order, marking orders if you will, and we must respond.
List to Paul in Rom. 1:14 and 1 Cor. 8:16 for NT parallels.

V. A "centered" call.
This call goes to the very core of our being because is it the very center of the gospel.
We get tired, pessimistic, spiritually discouraged. We may react as Jeremiah did. We may resemble Jonah. We may try to hid from God. Elijah escaped Jezebel and argued with God trying to justify his desertion. Some today have deserted the ranks, failed to answer the call, and are arguing with God about why they cannot be more generous, more involved, more active, more faithful. Others like Job and Jeremiah become discouraged and may even become spiritually rebellious.
Jeremiah was upset with God, 15:18. He discussed his dilemma with God, vowed to forget the call of God, but the fire was centered within him, and his identity as God's person in the very core of his being demanded that he respond, Jer. 23:29.

Conclusion
In the life of every servant of God, there are Gethsemanes of moral depression, mounts of optimism. In the middle of storms, there is always a calm from God. In the midst of darkness, light sines forth. A child of God cannot leave God because God is within us, central to our being and identity. He calls us--consumes us, continues with us, convicts us, calms us--in the very center of our being.
This truth is reflect in Jer. 20:7-9. The fire in Jeremiah's bones told him that God was there, in him, with him (1:8). Jeremiah knew God's presence. The storm left, the clouds of doubt lifted, and he could see God beside him, as he had always been (20:11).
God not only calls us, but promises his presence with us as we answer his call. God calls again today--continually, convicting, constraining by his love. Hearts want to answer, but remain still during invitation song after invitation song because of potential embarrassment, spiritual inertia, apathy, Satan's lies.
God calls us, and does not set before us anything that needs to done that cannot be done. Hearts want to answer to be baptized into Christ, but Satan says "wait" or "it's not important," or even "it is not necessary." Hearts want to answer to come home, but we older folks are just stuck. Hearts want to answer to be generous as our God has been generous with us, but our better judgment and common sense hold us back in preparation for the next depression. We are saving, and the words of Haggai convict us--pour bags have holes in them.
God calls us--to respond, to send the light, to name the name of Jesus in confession and baptism, and in evangelizing the whole world. Will you do what you hearts bid you do, as we stand and sing.