“Our union is now complete; our constitution composed, established, and approved. You are now the guardians of your own liberties. We may justly address you, as the decemviri did the Romans, and say,”

Speech before the Chamber of Commerce, Elmira, New York (3 May 1907); published in Addresses and Papers of Charles Evans Hughes, Governor of New York, 1906–1908 (1908), p. 139

Speech at Edwardsville, Illinois (11 September 1858); quoted in Lincoln, Abraham; Mario Matthew Cuomo, Harold Holzer, G. S. Boritt, Lincoln on Democracy http://books.google.de/books?id=8bWmmyJEMZoC&pg=PA128 (Fordham University Press, September 1, 2004), 128. .
Variant of the above quote: What constitutes the bulwark of our own liberty and independence? It is not our frowning battlements, our bristling sea coasts, our army and our navy. These are not our reliance against tyranny All of those may be turned against us without making us weaker for the struggle. Our reliance is in the love of liberty which God has planted in us. Our defense is in the spirit which prizes liberty as the heritage of all men, in all lands everywhere. Destroy this spirit and you have planted the seeds of despotism at your own doors. Familiarize yourselves with the chains of bondage and you prepare your own limbs to wear them. Accustomed to trample on the rights of others, you have lost the genius of your own independence and become the fit subjects of the first cunning tyrant who rises among you.
Fragment of Speech at Edwardsville, Ill., September 13, 1858; quoted in Lincoln, Abraham; The Writings of Abraham Lincoln V05 http://www.classic-literature.co.uk/american-authors/19th-century/abraham-lincoln/the-writings-of-abraham-lincoln-05/ebook-page-05.asp) p. 6-7
1850s
Context: What constitutes the bulwark of our own liberty and independence? It is not our frowning battlements, our bristling sea coasts, the guns of our war steamers, or the strength our gallant and disciplined army? These are not our reliance against a resumption of tyranny in our fair land. All of those may be turned against our liberties, without making us weaker or stronger for the struggle. Our reliance is in the love of liberty which God has planted in our bosoms. Our defense is in the preservation of the spirit which prizes liberty as the heritage of all men, in all lands, everywhere. Destroy this spirit, and you have planted the seeds of despotism around your own doors. Familiarize yourselves with the chains of bondage and you are preparing your own limbs to wear them. Accustomed to trample on the rights of those around you, you have lost the genius of your own independence, and become the fit subjects of the first cunning tyrant who rises.

For some, he concluded, this vote may be hard. But we have a mission and a mandate to be on the right side of history.
Source: Quoted in Impeachment is Over, But Don’t Despair by Diallo Brooks, CounterPunch https://www.counterpunch.org/2020/02/07/impeachment-is-over-but-dont-despair/, (7 Feb 2020)

Speech, United States Senate (11 March 1850).
Context: It is true, indeed, that the national domain is ours. It is true that it was acquired by the valor and with the wealth of the whole nation. But we hold no arbitrary authority over it. We hold no arbitrary authority over anything, whether lawfully acquired or seized by usurpation. The constitution regulates our stewardship; the constitution devotes the domain to union, to justice, to defense, to welfare and to liberty.
But there is a higher law than the Constitution, which regulates our authority over the domain, and devotes it to the same noble purposes.

2000s, The Real Abraham Lincoln: A Debate (2002), The Right of Secession Is Not the Right of Revolution

Book 5 Section 11
Tusculanae Disputationes – Tusculan Disputations (45 BC)

Second Reply to Hayne (1830)
Context: When my eyes shall be turned to behold for the last time the sun in heaven, may I not see him shining on the broken and dishonored fragments of a once glorious Union; on States dissevered, discordant, belligerent; on a land rent with civil feuds, or drenched, it may be, in fraternal blood! Let their last feeble and lingering glance rather behold the glorious ensign of the republic, now known and honored throughout the earth, still full high advanced, its arms and trophies streaming in the original lustre, not a stripe erased or polluted, nor a single star obscured, bearing for its motto, no such miserable interrogatory as 'What is all this worth?' nor those words of delusion and folly, 'Liberty first and Union afterward,'; but everywhere, spread over all the characters of living light, blazing on all its ample folds, as they float over the sea and over the land, and in every wind under the whole heavens, that other sentiment, dear to every true American heart, -- Liberty and Union, now and forever, one and inseparable!

Letter to Jean-Baptiste Le Roy (13 November 1789)
First published in The Private Correspondence of Benjamin Franklin (1817) p.266 https://books.google.de/books?id=jY8EAAAAYAAJ&pg=PA266&dq=constitution
The Yale Book of Quotations quotes “‘Tis impossible to be sure of any thing but Death and Taxes,” from Christopher Bullock, The Cobler of Preston (1716). The YBQ also quotes “Death and Taxes, they are certain,” from Edward Ward, The Dancing Devils (1724).
Epistles

Wayne Dyer, quoted in The Complete Idiot's Guide to Understanding Buddhism (2002) by Gary Gach, p. 285
Misattributed