In light of America's current war in Iraq and ongoing war against terrorism, the actions of our Founding Fathers in times of war are instructive. This is the text of the first national day of thanksgiving in America (set for December 18, 1777), declared by the Continental Congress on November 1, 1777:

IN CONGRESS

November 1, 1777

FORASMUCH as it is the indispensable Duty of all Men to adore the superintending Providence of Almighty God; to acknowledge with Gratitude their Obligation to him for benefits received, and to implore such farther Blessings as they stand in Need of; And it having pleased him in his abundant Mercy not only to continue to us the innumerable Bounties of his common Providence, but also to smile upon us in the Prosecution of a just and necessary War, for the Defence and Establishment of our unalienable Rights and Liberties; particularly in that he hath been pleased in so great a Measure to prosper the Means used for the Support of our Troops and to crown our Arms with most signal success:

It is therefore recommended to the legislative or executive powers of these United States, to set apart THURSDAY, the eighteenth Day of December next, for Solemn Thanksgiving and Praise; That with one Heart and one Voice the good People may express the grateful Feelings of their Hearts, and consecrate themselves to the Service of their Divine Benefactor; and that together with their sincere Acknowledgments and Offerings, they may join the penitent Confession of their manifold Sins, whereby they had forfeited every Favour, and their humble and earnest Supplication that it may please GOD, through the Merits of Jesus Christ, mercifully to forgive and blot them out of Remembrance; That it may please him graciously to afford his Blessing on the Governments of these States respectively, and prosper the public Council of the whole; to inspire our Commanders both by Land and Sea, and all under them, with that Wisdom and Fortitude which may render them fit Instruments, under the Providence of Almighty GOD, to secure for these United States the greatest of all human blessings, INDEPENDENCE and PEACE; That it may please him to prosper the Trade and Manufactures of the People and the Labour of the Husbandman, that our Land may yet yield its Increase; To take Schools and Seminaries of Education, so necessary for cultivating the Principles of true Liberty, Virtue and Piety, under his nurturing Hand, and to prosper the Means of Religion for the promotion and enlargement of that Kingdom which consisteth “in Righteousness, Peace and Joy in the Holy Ghost.”

And it is further recommended, that servile Labour, and such Recreation as, though at other Times innocent, may be unbecoming the Purpose of this Appointment, be omitted on so solemn an Occasion.

Extract from the Minutes,

This is text excerpted from a national fast declared by the Continental Congress on March 16, 1776:

IN CONGRESS

In times of impending calamity and distress; when the liberties of America are imminently endangered by the secret machinations and open assaults of an insidious and vindictive administration, it becomes the indispensable duty of these hitherto free and happy colonies, with true penitence of heart, and the most reverent devotion, publickly to acknowledge the over ruling providence of God; to confess and deplore our offences against him; and to supplicate his interposition for averting the threatened danger, and prospering our strenuous efforts in the cause of freedom, virtue, and posterity.
. . . Desirous, at the same time, to have people of all ranks and degrees duly impressed with a solemn sense of God's superintending providence, and of their duty, devoutly to rely, in all their lawful enterprizes, on his aid and direction, Do earnestly recommend, that Friday, the Seventeenth day of May next, be observed by the said colonies as a day of humiliation, fasting, and prayer; that we may, with united hearts, confess and bewail our manifold sins and transgressions, and, by a sincere repentance and amendment of life, appease his righteous displeasure, and, through the merits and mediation of Jesus Christ, obtain his pardon and forgiveness; humbly imploring his assistance to frustrate the cruel purposes of our unnatural enemies;
. . . that it may please the Lord of Hosts, the God of Armies, to animate our officers and soldiers with invincible fortitude, to guard and protect them in the day of battle, and to crown the continental arms, by sea and land, with victory and success: Earnestly beseeching him to bless our civil rulers, and the representatives of the people, in their several assemblies and conventions; to preserve and strengthen their union, to inspire them with an ardent, disinterested love of their country; to give wisdom and stability to their counsels; and direct them to the most efficacious measures for establishing the rights of America on the most honourable and permanent basis—That he would be graciously pleased to bless all his people in these colonies with health and plenty, and grant that a spirit of incorruptible patriotism, and of pure undefiled religion, may universally prevail; and this continent be speedily restored to the blessings of peace and liberty, and enabled to transmit them inviolate to the latest posterity. And it is recommended to Christians of all denominations, to assemble for public worship, and abstain from servile labour on the said day.