The Memorial Arch (constructed in 1889) of Washington Square Park in Greenwich Village reads:
 
“Let us raise a standard to which the wise and the honest can repair. The event is in the hand of God. — Washington.”
 
Gouverneur Morris (1752-1816) quoted this in a New York City oration for George Washington (1732-1799) on December 31, 1799. Washington’s remark was said to have been made at the 1787 Constitutional Convention, where Washington was president and Morris represented Pennsylvania. Unfortunately, there does not appear to be any other documentation of Washington’s statement.
 
Washington’s Constitutional Convention statement was seldom cited until 1889, the centennial anniversary of his presidential inauguration. Washington’s statement appears on the border of Violet Oakley’s painting, “The Creation and Preservation of the Union—George Washington at the Constitutional Convention” (commissioned in 1911).
 
 
Wikipedia: Washington Square Park
Washington Square Park is one of the best-known of New York City’s 1,900 public parks. At 9.75 acres (39,500 m2), it is a landmark in the Manhattan neighborhood of Greenwich Village, as well as a meeting place and center for cultural activity. It is operated by the New York City Department of Parks and Recreation.
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Construction of the arch
In 1889, to celebrate the centennial of George Washington’s inauguration as president of the United States, a large plaster and wood Memorial Arch was erected over Fifth Avenue just north of the park. The temporary plaster and wood arch was so popular that in 1892 a permanent marble arch, designed by the New York architect Stanford White, was erected, standing 77 feet (23 m). During the excavations for the eastern leg of the arch, human remains, a coffin and a gravestone dated 1803 were uncovered 10 feet (3 m) below ground level. The inscription on the arch reads:
 
Let us raise a standard to which the wise and the honest can repair. The event is in the hand of God. — Washington
 
Wikipedia; George Washington
George Washington (February 22, 1732 – December 14, 1799) was the dominant military and political leader of the new United States of America from 1775 to 1799. He led the American victory over Britain in the American Revolutionary War as commander-in-chief of the Continental Army in 1775–1783, and he presided over the writing of the Constitution in 1787. As the unanimous choice to serve as the first President of the United States (1789–1797), he developed the forms and rituals of government that have been used ever since, such as using a cabinet system and delivering an inaugural address. As President, he built a strong, well-financed national government that stayed neutral in the wars raging in Europe, suppressed rebellion and won acceptance among Americans of all types, but also saw the advent of contentious political parties. Washington was universally regarded as the “Father of his country”.
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1787: Constitutional Convention
Washington’s retirement to Mount Vernon was short-lived. He made an exploratory trip to the western frontier in 1784, was persuaded to attend the Constitutional Convention in Philadelphia in the summer of 1787, and was unanimously elected president of the Convention. He participated little in the debates (though he did vote for or against the various articles), but his high prestige maintained collegiality and kept the delegates at their labors. The delegates designed the presidency with Washington in mind, and allowed him to define the office once elected. After the Convention, his support convinced many to vote for ratification; the new Constitution was ratified by all thirteen states.
 
Wikipedia: Gouverneur Morris
Gouverneur Morris, often addressed as Gouv Morris (January 31, 1752 – November 6, 1816), was an American statesman, a Founding Father of the United States, and a native of New York City who represented Pennsylvania in the Constitutional Convention of 1787. Gouverneur (pronounced GOU VER NEHR) Morris was also an author of large sections of the Constitution of the United States and one of its signers. He is widely credited as the author of the document’s preamble: “We the People of the United States, in order to form a more perfect union ... ” and has been called the ‘Penman of the Constitution.’ In an era when most Americans thought of themselves as citizens of their respective states, Morris advanced the idea of being a citizen of a single union of states.
 
A gifted scholar, Morris enrolled in 1764 at the age of twelve at King’s College, now Columbia University in New York City. He graduated in 1768 and received a master’s degree in 1771.
     
Cornell University Library Internet Archive
The MEMORIAL ART GALLERY
ROCHESTER, NEW YORK
CATALOGUE OF AN EXHIBITION OF OIL PAINTINGS BY GEORGE BELLOWS, N. A. AND MURAL PAINTINGS AND DRAWINGS BY VIOLET OAKLEY
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VIOLET OAKLEY
Born New York. Pupil of Art Students’ League, New- York; Pennsylvania Academy of the Fine Arts; AmanJean., Collin and Lazar, Paris; Howard Pyle, Philadelphia. Member: Philadelphia Water Color Club; Fellowship, Pennsylvania Academy of the Fine Arts; New York Water Color Club; Plastic Club of Philadelphia; Society of Illustrators, New York (associate), 1904; National Society of Mural Painters; American Institute of Architects (honorary) ; Art Alliance of Philadelphia; Associate, National Academy of Design, 1918; Litt. D., Delaware College, 1918. Awards: Gold medal for illustration and silver medal for mural decoration, St. Louis Exposition,, 1904; gold medal of honor, Pennsylvania Academy of the Fine Arts, 1905; gold medal of honor, Panama-Pacific International Exposition, San Francisco, 1915; medal of honor for painting, New York Architectural League, 1916.
 
23. The Constitutional Convention and the Creation of the true Union, — Philadelphia, May, 1787.
[Copley Print, Original painting, 10’xl7’.]
“Let us raise a standard to which the wise and honest can repair. The event is in the hand of God.”
   
Google Books
Eulogies and orations on the life and death of General George Washington, first president of the United States of America
By Manning & Loring,; W.P. & L. Blake (Firm),
Boston, MA: Printed by Manning & Loring, for W.P. & L. Blake, No. 1, Cornhill, : and Manning & Loring, No. 2, Cornhill
1800
Pg. 44:
An Oration
UPON THE DEATH OF GENERAL WASHINGTON,
Delivered at the Request of the Corporation of the City of
NEW-YORK,
On the 31st of December, 1799.
BY GOUVERNEUR MORRIS
Pg. 52:
“It is (said he) too probable that no plan we propose will be adopted. Perhaps another dreadful conflict is to be sustained. If, to please the people, we offer what (Pg. 118—ed.) we ourselves disapprove, how can we afterwards defend our work? Let us raise a standard to which the wise and the honest can repair. The event is in the hand of God.”
 
Google Books
The Washingtoniana:
Containing a sketch of the life and death of the late Gen. George Washington, with a collection of elegant eulogies, orations, poems, &c., sacred to his memory.
By Francis Johnston and William Hamilton
Lancaster, PA: Printed and sold by William Hamilton
1802
Pg. 117:
“It is (said he) too probable that no plan we propose will be adopted. Perhaps another dreadful conflict is to be sustained. If, to please the people, we offer what (Pg. 118—ed.) we ourselves disapprove, how can we afterwards defend our work? Let us raise a standard to which the wise and the honest can repair. The event is in the hand of God.”
 
Google Books
An oration delivered on the Fourth of July, 1804, at St. Peter’s church in Salem, Massachusetts: in commemoration of the independence of the United States
By John Pickering; University of Missouri—Columbia. Libraries. Fourth of July Orations Collection.
Salem, MA: Printed by Joshua Cushing
1804
Cover page:
“If to please the people, we offer what we ourselves disapprove, how can we afterwards defend our work? Let us raise a standard to which the WISE and the HONEST can repair: The event is in the hand of God.”
WASHINGTON.