Christians also have prayer...

Christians also have prayer. Christ will speak of this later. Through prayer they obtain for themselves and for others all that they ask of God, even physical things. This is one of the greatest works they do to help and preserve the world, even if they did nothing else. Thus when a Christian subject prays, and the prince is victorious over his enemies, who, then, actually defeated the enemies and achieved the victory? No other than the Christian, even if no one gives him credit and he gains neither reputation nor honor because of it. God did not grant victory for the sake of the prince?if he was an unbeliever?but in answer to the prayer of this one Christian. So greatly can a whole country or kingdom be benefited by one pious man, for whose sake all are blessed. This we find illustrated in Gen. 14:14 by the story of Abraham; also in the story of Lot, which is recorded in Gen. 19:22, where we read that Sodom and Gomorrah were spared while Lot still lived there. And in 2 Kings 5:1 we read that because of Naaman alone God bestowed good fortune and victory on the entire kingdom of Syria, which, after all, was idolatrous. According to Gen. 41:46 ff., all Egypt was helped because of Joseph. The kingdom of Persia fared similarly for the sake of Daniel. And the prophet Isaiah defeated the hosts of the Assyrian emperor singlehandedly through his prayer. Thus in times gone by good fortune and victory in war were often granted to the Romans, the Persians, and others solely for the sake of the Christians.

With these and the following words Christ also demonstrates what constitutes a Christian's true office and function, and how necessary the exercise of this is in Christendom. The prophet Zechariah refers to this when he says (12:10) that Christ will pour out and grant the spirit which is called "a spirit of compassion and supplication." For in all Christians He will effect and produce these two things: First, He will convince and assure their hearts that they have a compassionate God; secondly, He will enable them to help others by their supplication. The result of the first is that they are reconciled to God and have all they need for themselves. Then, when they have this, they will become gods and will be saviors of the world by their supplication. Through the spirit of compassion they themselves will become children of God; and then, as children of God, they will mediate between God and their neighbor, and will serve others and help them attain this estate too.

For once a Christian begins to know Christ as his Lord and Savior, through whom he is redeemed from death and brought into His dominion and inheritance, God completely permeates his heart.51 Now he is eager to help everyone acquire the same benefits. For his greatest delight is in this treasure, the knowledge of Christ. Therefore he steps forth boldly, teaches and admonishes others, praises and confesses his treasure before everybody, prays and yearns that they, too, may obtain such mercy. There is a spirit of restlessness amid the greatest calm, that is, in Gods grace and peace. A Christian cannot be still or idle. He constantly strives and struggles with all his might, as one who has no other object in life than to disseminate God's honor and glory among the people, that others may also receive such a spirit of grace and through this spirit also help him pray. For wherever the spirit of grace resides, there we can and dare, yes, must begin to pray.

Therefore Christ wants to say here: "When you believe in Me and have received the spirit by which the heart is assured of the grace of God (Christ had said above: "He who has seen Me has seen the Father"), then you will certainly be constrained to pray." For prayer is the true work characteristic only of Christians. Before we become Christians and believe, we do not know how or what to pray. And even if a man prays most fervently, the spirit of grace is not yet present. Then the heart is still disposed to say: "Dear Lord, I ask you to regard my life, my intense suffering, or the merit of this or of that saint, the intercession and the good works of pious people." This is not faith in divine grace and mercy through Christ. Moreover, the heart always remains in doubt and cannot conclude that its prayer has certainly been heard. It insists on dealing with God on the basis of its own holiness or that of others, and without Christ, as though God had to humble Himself before it, have His grace or assistance wrested from Him, and thus become our debtor and servant. This means deserving wrath, not grace; this means mocking God, not praying to Him.

A genuinely Christian prayer must issue from the spirit of grace, which says: "I have lived my best; therefore I implore Thee not to regard my life and my conduct, but Thy mercy and compassion promised me in Christ, and because of this to grant me the fulfillment of my prayer." Thus our prayer must, in real and sincere humility, take no account of ourselves; it must rely solely and confidently on the promise of grace, in the firm trust that God will hear us, as He has commanded us to pray and has promised to hear us.

Thus you must learn from this text that through Christ alone we possess both grace and the granting of prayer, that we first become children of God, entitled to call upon Him, and then also receive what we need for ourselves and for others. Therefore wherever there is a Christian, there is none other than the Holy Spirit, who does nothing but pray without ceasing. Even though one does not move one's lips and form words continuously, one's heart nonetheless does beat incessantly; and, like the pulse and the heart in the body, it beats with sighs such as these: "Oh, dear Father, please let Thy name be hallowed, Thy kingdom come, Thy will be done among us and everyone!" And when blows fall, when temptations thicken, and adversity presses harder, then such sighing prayers become more fervent and also find words. A Christian without prayer is just as impossible as a living person without a pulse. The pulse is never motionless; it moves and beats constantly, whether one is asleep or something else keeps one from being aware of it. -Martin
Luther, LW 24:87-88.