“Free trade is not based on utility but on justice.”

Source: (1776), Book V, Chapter II, Part II, p. 894.

On Import Duties (25 April 1843). Compare: "It is a condition which confronts us, not a theory" (Grover Cleveland, Annual Message, 1887, in reference to the tariff); "Protection is not a principle but an expedient" (below).
1840s

Source: Bad Samaritans: The Myth of Free Trade and the Secret History of Capitalism (2008), Ch. 3, More trade, fewer ideologies, p. 83
Context: The importance of international trade for economic development cannot be overemphasized. But free trade is not the best path to economic development. Trade helps economic development only when the country employs a mixture of protection and open trade, constantly adjusting it according to its changing needs and capabilities. Trade is simply too important for economic development to be left to free trade economists.

Source: Sociology For The South: Or The Failure Of A Free Society (1854), p. 61

Speech to the Conservative Party Conference in Bournemouth (4 October 1935), quote in The Times (5 October 1935), p. 17.
1935
Context: Trade unionism, like friendly societies, is a peculiarly English growth. This country is the native soil in which such democratic institutions are indigenous. They are an integral part of the country's life, and they are a great stabilizing influence... Watch carefully the continuous efforts that are made by the Communist Party in this country to get control of and to destroy trade unionism. They do not want to destroy it for nothing. A free trade unionism is a bulwark of popular liberty. If trade unionism were destroyed you would be a long way on the road to Communism, and via Communism to Fascism.

2000s, Where the Right Went Wrong (2004)

"What should trade negotiators negotiate about?" Journal of Economic Literature, Vol. 35, No. 1 (Mar., 1997)

Speech in Manchester (21 April 1908), quoted in Thomas Jones, Lloyd George (London: Oxford University Press, 1951), p. 35.
Chancellor of the Exchequer