They had the courage not only, but they had the almost infinite wisdom, to declare that all men are created equal. Such things had occasionally been said by some political enthusiast in the olden time, but, for the first time in the history of the world, the representatives of a nation, the representatives of a real, living, breathing, hoping people, declared that all men are created equal. With one blow, with one stroke of the pen, they struck down all the cruel, heartless barriers that aristocracy, that priestcraft, that kingcraft had raised between man and man. They struck down with one immortal blow that infamous spirit of caste that makes a god almost a beast, and a beast almost a god. With one word, with one blow, they wiped away and utterly destroyed, all that had been done by centuries of war — centuries of hypocrisy — centuries of injustice.
One hundred years ago our fathers retired the gods from politics.

Robert Green Ingersoll (1833-1899) American lawyer, freethinker, orator

Speech (1876-07-04), “Centennial Oration [The Declaration of Independence],” Peoria, Illinois
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In quotation collections, this last phrase is often concatenated with the first sentence of the speech:

One hundred years ago, our fathers retired the gods from politics. The Declaration of Independence is the grandest, the bravest, and the profoundest political document that was ever signed by the representatives of a people. It is the embodiment of physical and moral courage and of political wisdom.