An act against the Constitution is void; an act against natural equity is void.
Argument Against the Writs of Assistance (1761)
ALL PRECEDENTS ARE UNDER THE CONTROUL OF THE PRINCIPLES OF THE LAW... No Acts of Parliament can establish such a writ [writ of assistance enabling British search of homes for no reason]: … it would be void, "AN ACT AGAINST THE CONSTITUTION IS VOID." Vid. Viner. But … special writs may be granted on oath and probable suspicion.
Massachusetts Spy (April 29, 1773)(Principle of judicial review. In addition, much like the prohibition of unreasonable searches and seizures under the Fourth Amendment of the US Constitution).
... [Slave] trade … is the most shocking violation of the law of nature, has a direct tendency to diminish … liberty, and makes every dealer in it a tyrant, from the director of an African company to the petty chapman [peddler]…. It is a clear truth, that those who every day barter away other men's liberty will soon care little for their own.
The Rights of British Colonists Asserted (1764)
If we are not represented, we are slaves.
Report on the Sugar Act (13 June 1764)
Taxation without representation is tyranny.
Attributed as a statement by Otis in court in 1761, but no record of the remark has been found prior to notes written by John Adams in 1820.
A man's house is his castle.
Not original to Otis, but a familiar proverb dating as far back as the 16th century