“Prosperity is the best protector of principle.”

Kudlow's Money Politics blog http://kudlowsmoneypolitics.blogspot.com/2007/09/free-market-hall-of-fame.html, September 14, 2007. (known as the "Kudlow Creed" on the Kudlow & Company show)

Speech in the House of Commons (18 May 1851), quoted in George Henry Francis, Opinions and Policy of the Right Honourable Viscount Palmerston, G.C.B., M.P., &c. as Minister, Diplomatist, and Statesman, During More Than Forty Years of Public Life (London: Colburn and Co., 1852), pp. 429-430.
1850s
Context: It is only from England, and from the exertions of England, that any hope can be entertained of the extinction of the slave trade, and of the ultimate abolition of slavery throughout the world; because it is England alone that feels any deep and sincere interest in the matter. England now holds a proud position among the nations of the earth, and exercises a great influence upon the destinies of mankind. That influence is owing, in the first place, to our great wealth, to our unbounded resources, to our military and naval strength. But it is owing still more, if possible, to the moral dignity which marks the character and conduct of the British people... Those who desire to see the principles of liberty thrive and extend through the world, should cherish, with an almost religious veneration, the prosperity and greatness of England. So long as England shall ride preeminent on the ocean of human affairs, there can be none whose fortunes shall be so shipwrecked—there can be none whose condition shall be so desperate and forlorn—that they may not cast a look of hope towards the light that beams from hence; and though they may be beyond the reach of our power, our moral support and our sympathy shall cheer them in their adversity, and shall assist them to bear up, and to hold out, waiting for a better day.

First reported in the Annual Report of the Massachusetts Bible Society (1870), p. 27. This is actually a misquote combining phrases from different lines in an address delivered by Webster to the New York Historical Society on February 23, 1852.
Misattributed

Source: Sustainable History and the Dignity of Man (2009), p.28

2015, Remarks to the People of Africa (July 2015)
Context: [... ] let girls learn so they grow up healthy and they grow up strong. And that will be good for families. And they will raise smart, healthy children, and that will be good for every one of your nations. Africa is the beautiful, strong women that these girls grow up to become. The single best indicator of whether a nation will succeed is how it treats its women. When women have health care and women have education, families are stronger, communities are more prosperous, children do better in school, nations are more prosperous. Look at the amazing African women here in this hall. If you want your country to grow and succeed, you have to empower your women. […] Let’s work together to stop sexual assault and domestic violence. Let’s make clear that we will not tolerate rape as a weapon of war -- it’s a crime. And those who commit it must be punished.  Let’s lift up the next generation of women leaders who can help fight injustice and forge peace and start new businesses and create jobs -- and some might hire some men, too. We’ll all be better off when women have equal futures.

VPRO, (1991)

The Harsh Reality Of Regulating Overtime Pay http://www.forbes.com/sites/realspin/2016/05/18/the-harsh-reality-of-regulating-overtime-pay/#22d4f5c12321 (May 18, 2016)

Slavery (1835)
Context: There are times when the assertion of great principles is the best service a man can render society. The present is a moment of bewildering excitement, when men's minds are stormed and darkened by strong passions and fierce conflicts; and also a moment of absorbing worldliness, when the moral law is made to bow to expediency, and its high and strict requirements are denied, or dismissed as metaphysical abstractions or impracticable theories. At such a season, to utter great principles without passion, and in the spirit of unfeigned and universal good-will, and to engrave them deeply and durably on men's minds, is to do more for the world, than to open mines of wealth, or to frame the most successful schemes of policy.

Optimism (1903)
Context: The highest result of education is tolerance. Long ago men fought and died for their faith; but it took ages to teach them the other kind of courage, — the courage to recognize the faiths of their brethren and their rights of conscience. Tolerance is the first principle of community; it is the spirit which conserves the best that all men think.