The U.S. Constitution grants Congress the power of the purse—that is, Congress must authorize how money is raised and spent. The term “power of the purse” dates to at least the 1600s, when it was used in England and compared to the power of the sword.
 
   
Wikipedia: Power of the purse
The power of the purse is the ability of one group to manipulate and control the actions of another group by withholding funding, or putting stipulations on the use of funds. The power of the purse can be used positively (e.g. awarding extra funding to programs that reach certain benchmarks) or negatively (e.g. removing funding for a department or program, effectively eliminating it). The power of the purse is most often utilized by forces within a government that do not have direct executive power but have control over budgets and taxation.
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In the United States
The power of the purse plays a critical role in the relationship of the United States Congress and the President of the United States, and has been the main historic tool by which Congress can limit executive power. One of the most recent examples is the Foreign Assistance Act of 1974, which eliminated all military funding for the government of South Vietnam and thereby ended the Vietnam War. Other recent examples include limitations on military funding placed on Ronald Reagan by Congress, which led to the withdrawal of United States Marines from Lebanon. Appropriation bills cannot originate in the Senate, but the Senate can amend appropriation bills that originate in the House.
 
Dictionary.com
power of the purse definition
The influence that legislatures have over public policy because of their power to vote money for public purposes. The United States Congress must authorize the president’s budget requests to fund agencies and programs of the executive branch.
 
Google Books
BibliothecaPpolitica:
or, An enquiry into the ancient constitution of the English Government
By James Tyrrell
London: R. Baldwin
1694
Pg. 941:
... thereby to hinder us from joining against him; then by rendring the King Absolute to take them quite away, and put the sole power of the Purse as well as of the Sword wholly into his Hands.
   
Google Books
A Collection of the Writings of the Author of the True-born English-Man
(By Daniel Defoe—ed.)
London
1703
Pg. 216:
But We are told, The Power of the Purse is not a sufficient Security without the power of the Sword: ...
 
Google Books
An Enquiry Into the Causes of the Late Increase of Robbers, &c
By Henry Fielding
London: A, Millar
1751
Pg. XXVI:
To put this in the clearest Light: There appear to me to be Four Sorts of Political Power; that of bodily Strength, that of the Mind, the Power of the Purse, and the Power of the Sword.
   
Google Books
March 1784, The London Magazine, Or, Gentleman’s Monthly Intelligencer, pg. 219:
To put this in the cleared light: there appear to me to be four sorts of political power; that of bodily strength, that of the mind, the power of the purse, and the power of the sword.
 
Google Books
April 1793, Gentleman’s Magazine and Historical Chronicle, “Review of New Publications,” pg. 347:
“Examine the House of Commons in what light you will, and it will be found to possess in the power of the purse so enormous an authority that the other branches of the legislature are absolutely at its mercy” (p. 68).
 
Google Books
A General Collection of the Best and Most Interesting Voyages and Travels in All Parts of the World
(Volume 4)
By John Pinkerton
London: Longman, Hurst, Rees, and Orme
1809
Pg. 193:
The purse— the power of the purse is every thing; skilfully managed, with so necessitous a government as ours, it would, one after another, have gained all we wished.
 
OCLC WorldCat record
The power of the purse considered constitutionally
Author: T T A’Beckett
Publisher: Melbourne : Samuel Mullen, 1867.
Edition/Format:   Book : English
 
OCLC WorldCat record
The Power of the Purse. [A tale.] By “Actinotus.”.
Author: ACTINOTUS, pseud.
Publisher: London : Swan Sonnenschein & Co., 1897.
Edition/Format:   Book : English
 
OCLC WorldCat record
The power of the purse; a brief study of constitutional history, with appendix containing a list of the names of the constituencies returning members to the House of Commons, county by county, in nine selected parliaments from 1295 to 1868,
Author: Henry James Robinson
Publisher: London, J. Murray [1928]
Edition/Format:   Book : English
 
OCLC WorldCat record
The power of the purse; a history of American public finance, 1776-1790.
Author: E James Ferguson
Publisher: Chapel Hill, Published for the Institute of Early American History and culture at Williamsburg, Va., by the University of North Carolina Press [1961]
Edition/Format:   Book : English
 
OCLC WorldCat record
The power of the purse; appropriations politics in Congress
Author: Richard F Fenno
Publisher: Boston, Little, Brown [1966]
Edition/Format:   Book : English
 
OCLC WorldCat record
The Power of the purse
Author: Edwin Newman; Norman J Ornstein
Publisher: Washington, D.C. : WETA, ©1983.
Series: Congress, we the people, Program 25.
Edition/Format:   Video : Videocassette Visual material : EnglishView all editions and formats
Summary:
This discusses Congressional control of the Federal budget, procedures and organizations involved in budgeting, the 1974 Budget Act, changes since then in Presidential relations, cohesion of Congress. It includes the following topics : the president proposes, the budget ary process, a case study, defense budgeting and an evaluation of congressional budgeting.
 
Google Books
Daybreak:
Undoing the Imperial Presidency and Forming a More Perfect Union
By David Swanson
New York, NY: Seven Stories Press
2009
Pg. 54:
These congressional prerogatives are commonly known as “the power of the purse.” That phrase is often used to describe not simply the power to determine how money is spent, but the technique of using that power to restrain illegal activities by the president.