Psalm 138:1-8, I will give thee thanks, O Lord, with my whole heart; and I will sing psalms to thee before the angels; for thou hast heard all the words of my mouth. I will worship toward thy holy temple, and give thanks to thy name, on account of thy mercy and thy truth; for thou hast magnified thy holy name above every thing. In whatsoever day I shall call upon thee, hear me speedily; thou shalt abundantly provide me with thy power in my soul. Let all the kings of the earth, O Lord, give thanks unto thee; for they have heard all the words of thy mouth. And let them sing in the ways of the Lord; for great is the glory of the Lord.

For the Lord is high, and yet regards the lowly; and he knows high things from afar off. Though I should walk in the midst of affliction, thou wilt quicken me; thou hast stretched forth thine hands against the wrath of mine enemies, and thy right hand has saved me. O Lord, thou shalt recompense them on my behalf: thy mercy, O Lord, endures for ever: overlook not the works of thine hands.

Since 1623 our civil magistrates have issued proclamations setting apart a day of Thanksgiving and Prayer. The first being Governor William Bradford's Thanksgiving Proclamation:

Inasmuch as the great Father has given us this year an abundant harvest of Indian corn, wheat, peas, beans, squashes, and garden vegetables, and has made the forests to abound with game and the sea with fish and clams, and inasmuch as he has protected us from the ravages of the savages, has spared us from pestilence and disease, has granted us freedom to worship God according to the dictates of our own conscience.

Now I, your magistrate, do proclaim that all ye Pilgrims, with your wives and ye little ones, do gather at ye meeting house, on ye hill, between the hours of 9 and 12 in the day time, on Thursday, November 29th, of the year of our Lord one thousand six hundred and twenty-three and the third year since ye Pilgrims landed on ye Pilgrim Rock, there to listen to ye pastor and render thanksgiving to ye Almighty God for all His blessings. --William Bradford Ye Governor of Ye Colony

President George Washington’s Thanksgiving Proclamation 1789:

Whereas it is the duty of all nations to acknowledge the providence of Almighty God, to obey His will, to be grateful for His benefits, and humbly to implore His protection and favor; and Whereas both Houses of Congress have, by their joint committee, requested me to "recommend to the people of the United States a day of public thanksgiving and prayer, to be observed by acknowledging with grateful hearts the many and signal favors of Almighty God, especially by affording them an opportunity peaceably to establish a form of government for their safety and happiness:"

Now, therefore, I do recommend and assign Thursday, the 26th day of November next, to be devoted by the people of these States to the service of that great and glorious Being who is the beneficent author of all the good that was, that is, or that will be; that we may then all unite in rendering unto Him our sincere and humble thanks for His kind care and protection of the people of this country previous to their becoming a nation; for the signal and manifold mercies and the favorable interpositions of His providence in the course and conclusion of the late war; for the great degree of tranquility, union, and plenty which we have since enjoyed; for the peaceable and rational manner in which we have been enable to establish constitutions of government for our safety and happiness, and particularly the national one now lately instituted for the civil and religious liberty with which we are blessed, and the means we have of acquiring and diffusing useful knowledge; and, in general, for all the great and various favors which He has been pleased to confer upon us.

And also that we may then unite in most humbly offering our prayers and supplications to the great Lord and Ruler of Nations and beseech Him to pardon our national and other transgressions; to enable us all, whether in public or private stations, to perform our several and relative duties properly and punctually; to render our National Government a blessing to all the people by constantly being a Government of wise, just, and constitutional laws, discreetly and faithfully executed and obeyed; to protect and guide all sovereigns and nations (especially such as have shown kindness to us), and to bless them with good governments, peace, and concord; to promote the knowledge and practice of true religion and virtue, and the increase of science among them and us; and, generally to grant unto all mankind such a degree of temporal prosperity as He alone knows to be best.

Given under my hand, at the city of New York, the 3d day of October, A.D. 1789.

Abraham Lincoln’s Thanksgiving Proclamation 1863:

The year that is drawing toward its close has been filled with the blessings of fruitful fields and healthful skies. To these bounties, which are so constantly enjoyed that we are prone to forget the source from which they come, others have been added, which are of so extraordinary a nature that they cannot fail to penetrate and soften the heart which is habitually insensible to the ever-watchful providence of Almighty God.

In the midst of a civil war of unequaled magnitude and severity, which has sometimes seemed to foreign states to invite and provoke their aggressions, peace has been preserved with all nations, order has been maintained, the laws have been respected and obeyed, and harmony has prevailed everywhere, except in the theater of military conflict; while that theater has been greatly contracted by the advancing armies and navies of the Union.

Needful diversions of wealth and of strength from the fields of peaceful industry to the national defense have not arrested the plow, the shuttle, or the ship; the ax has enlarged the borders of our settlements, and the mines, as well of iron and coal as of the precious metals, have yielded even more abundantly than heretofore. Population has steadily increased, notwithstanding the waste that has been made in the camp, the siege, and the battlefield, and the country, rejoicing in the consciousness of augmented strength and vigor, is permitted to expect continuance of years with large increase of freedom.

No human counsel hath devised, nor hath any mortal hand worked out these great things. They are the gracious gifts of the Most High God, who while dealing with us in anger for our sins, hath nevertheless remembered mercy.

It has seemed to me fit and proper that they should be solemnly, reverently, and gratefully acknowledged as with one heart and one voice by the whole American people. I do, therefore, invite my fellow-citizens in every part of the United States, and also those who are at sea and those who are sojourning in foreign lands, to set apart and observe the last Thursday of November next as a Day of Thanksgiving and Praise to our beneficent Father who dwelleth in the heavens. And I recommend to them that, while offering up the ascriptions justly due to Him for such singular deliverances and blessings, they do also, with humble penitence for our national perverseness and disobedience, commend to His tender care all those who have become widows, orphans, mourners, or sufferers in the lamentable civil strife in which we are unavoidably engaged, and fervently implore the interposition of the Almighty hand to heal the wounds of the nation, and to restore it, as soon as may be consistent with the Divine purposes, to the full enjoyment of peace, harmony, tranquility, and union.

In testimony whereof, I have hereunto set my hand and caused the seal of the United Stated States to be affixed.

Done at the city of Washington, this third day of October, in the year of our Lord one thousand eight hundred and sixty-three, and of the Independence of the United States the eighty-eighth.

Abraham Lincoln

Barack Obama’s Thanksgiving Proclamation of 2012:

On Thanksgiving Day, Americans everywhere gather with family and friends to recount the joys and blessings of the past year. This day is a time to take stock of the fortune we have known and the kindnesses we have shared, grateful for the God-given bounty that enriches our lives. As many pause to lend a hand to those in need, we are also reminded of the indelible spirit of compassion and mutual responsibility that has distinguished our Nation since its earliest days.

Many Thanksgivings have offered opportunities to celebrate community during times of hardship. When the Pilgrims at Plymouth Colony gave thanks for a bountiful harvest nearly four centuries ago, they enjoyed the fruits of their labor with the Wampanoag tribe -- a people who had shared vital knowledge of the land in the difficult months before. When President George Washington marked our democracy's first Thanksgiving, he prayed to our Creator for peace, union, and plenty through the trials that would surely come. And when our Nation was torn by bitterness and civil war, President Abraham Lincoln reminded us that we were, at heart, one Nation, sharing a bond as Americans that could bend but would not break. Those expressions of unity still echo today, whether in the contributions that generations of Native Americans have made to our country, the Union our forebears fought so hard to preserve, or the providence that draws our families together this season.

As we reflect on our proud heritage, let us also give thanks to those who honor it by giving back. This Thanksgiving, thousands of our men and women in uniform will sit down for a meal far from their loved ones and the comforts of home. We honor their service and sacrifice. We also show our appreciation to Americans who are serving in their communities, ensuring their neighbors have a hot meal and a place to stay. Their actions reflect our age-old belief that we are our brothers' and sisters' keepers, and they affirm once more that we are a people who draw our deepest strength not from might or wealth, but from our bonds to each other.

On Thanksgiving Day, individuals from all walks of life come together to celebrate this most American tradition, grateful for the blessings of family, community, and country. Let us spend this day by lifting up those we love, mindful of the grace bestowed upon us by God and by all who have made our lives richer with their presence.

NOW, THEREFORE, I, BARACK OBAMA, President of the United States of America, by virtue of the authority vested in me by the Constitution and the laws of the United States, do hereby proclaim Thursday, November 22, 2012, as a National Day of Thanksgiving. I encourage the people of the United States to join together -- whether in our homes, places of worship, community centers, or any place of fellowship for friends and neighbors -- and give thanks for all we have received in the past year, express appreciation to those whose lives enrich our own, and share our bounty with others.

IN WITNESS WHEREOF, I have hereunto set my hand this twentieth day of November, in the year of our Lord two thousand twelve, and of the Independence of the United States of America the two hundred and thirty-seventh.