The principle of Toryism is mistrust of the people, qualified by fear; the principle of Liberalism is trust in the people, qualified by prudence.

William Gladstone (1809-1898) English Liberal politician, Prime Minister (1868-74, 1880-85, 1886, 1892-94)

Inscription on bust, National Liberal Club, London
    (Source)

This quotation, or versions of it, are certainly associated to Gladstone, but with enough variants to make concrete attribution difficult. Sometimes given with "Conservatism" substituted for "Toryism." Sometimes quoted in the opposite order. Some renditions use "tempered" rather than "qualified" for one or the other clause, e.g.,:

Liberalism is trust of the people, tempered by prudence; Conservatism, distrust of the people, tempered by fear.

The principle of Liberalism is trust in the people, qualified by prudence. The principle of Conservatism is mistrust of the people qualified by fear.

One party is influenced by trust of the people tempered by prudence, the other by distrust of the people tempered by fear.

The phrase has been attributed to speeches given in Oxford and Chester and in disparate dates from 1866, to 1872, to 1877. It is altogether likely he used different variations at multiple times. Two uses where I could find decent citations:

I think that the principle of the Conservative Party is jealousy of liberty and of the people, only qualified by fear; but I think the principle of the Liberal Party is trust in the people, only qualified by prudence.
[Speech, Opening of the Palmerston Club, Oxford (Dec 1878)]

[His policy of] trust in the people, tempered by prudence, and averse to violent and hasty change.
[Manifesto to the Electors of South-West Lancashire (1866)]