This was originally 21 quotes, but I've added to the list. If you have a favorite quote about liberty and freedom, please leave it in the comments or send it to me so I can add it to this post.
“He that would make his own liberty secure, must guard even his enemy from opposition; for if he violates this duty he establishes a precedent that will reach himself.” – Thomas Paine
“A man's country is not a certain area of land, of mountains, rivers, and woods, but it is a principle; and patriotism is loyalty to that principle.” – George William Curtis
“America is much more than a geographical fact. It is a political and moral fact – the first community in which men set out in principle to institutionalize freedom, responsible government, and human equality.” – Adlai Stevenson
“America is the greatest, freest and most decent society in existence. It is an oasis of goodness in a desert of cynicism and barbarism. This country, once an experiment unique in the world, is now the last best hope for the world.” – Dinesh D'Souza
“America was not built on fear. America was built on courage, on imagination and an unbeatable determination to do the job at hand.” – H.S. Truman
“Years ago, a group of good, wise, brave, God-fearing men stood up to claim and defend the human right for independence. Those men are now dead. Their work is not. But if good, wise, brave, God-fearing men fail to stand up in their stead, that independence will cease to exist.” – Richelle E. Goodrich
“Better to starve free than be a fat slave.” – Aesop
“Everything that is really great and inspiring is created by the individual who can labor in freedom.” – Albert Einstein
“Freedom consists not in doing what we like, but in having the right to do what we ought.” – Pope John Paul II
“Freedom has its life in the hearts, the actions, the spirit of men and so it must be daily earned and refreshed – else like a flower cut from its life-giving roots, it will wither and die.” – Dwight D. Eisenhower
“Freedom is never voluntarily given by the oppressor; it must be demanded by the oppressed.” – Martin Luther King, Jr.
“You have to love a nation that celebrates its independence every July 4, not with a parade of guns, tanks, and soldiers who file by the White House in a show of strength and muscle, but with family picnics where kids throw Frisbees, the potato salad gets iffy, and the flies die from happiness. You may think you have overeaten, but it is patriotism.” – Erma Bombeck
“Liberty is always dangerous, but it is the safest thing we have.” – Harry Emerson Fosdick
“Those who won our independence believed liberty to be the secret of happiness and courage to be the secret of liberty.” – Louis D. Brandeis
“We on this continent should never forget that men first crossed the Atlantic not to find soil for their ploughs but to secure liberty for their souls.” – Robert J. McCracken
“I prefer liberty with danger to peace with slavery.” – Unknown
“Where liberty dwells, there is my country.” – Benjamin Franklin
“The United States is the only country with a known birthday.” – James G. Blaine
“My God! How little do my countrymen know what precious blessings they are in possession of, and which no other people on earth enjoy!” – Thomas Jefferson
“What is the essence of America? Finding and maintaining that perfect, delicate balance between freedom ‘to’ and freedom ‘from’.” – Marilyn vos Savant
“Those who deny freedom to others deserve it not for themselves.” – Abraham Lincoln
“Freedom is never voluntarily given by the oppressor; it must be demanded by the oppressed.” – Martin Luther King, Jr.