“This was a good week’s labour.”

Speech in Limehouse, East London (30 July 1909), quoted in Better Times: Speeches by the Right Hon. D. Lloyd George, M.P., Chancellor of the Exchequer (London: Hodder & Stoughton, 1910), p. 155.
Chancellor of the Exchequer

Shadrach (1957)

TV Series and Specials (Includes DVDs), Trick of the Mind (2004–2006)

Harold Wilson, Memoirs 1916-1964: The Making of a Prime Minister (Weidenfeld & Nicolson and Michael Joseph, London, 1986), p. 121.
Attributed

The Collected Works of Abraham Lincoln edited by Roy P. Basler, Volume I, "Fragments of a Tariff Discussion" (1 December 1847)
1840s

The Notebooks of Leonardo da Vinci (1883), XIX Philosophical Maxims. Morals. Polemics and Speculations.

The Principles of Success in Literature (1865)
Context: It is impossible to deny that dishonest men often grow rich and famous, becoming powerful in their parish or in parliament. Their portraits simper from shop windows; and they live and die respected. This success is theirs; yet it is not the success which a noble soul will envy. Apart from the risk of discovery and infamy, there is the certainty of a conscience ill at ease, or if at ease, so blunted in its sensibilities, so given over to lower lusts, that a healthy instinct recoils from such a state. Observe, moreover, that in Literature the possible rewards of dishonesty are small, and the probability of detection great. In Life a dishonest man is chiefly moved by desires towards some tangible result of money or power; if he get these he has got all. The man of letters has a higher aim: the very object of his toil is to secure the sympathy and respect of men; and the rewards of his toil may be paid in money, fame, or consciousness of earnest effort. The first of these may sometimes be gained without Sincerity. Fame may also, for a time, be erected on an unstable ground, though it will inevitably be destroyed again. But the last and not least reward is to be gained by every one without fear of failure, without risk of change. Sincere work is good work, be it never so humble; and sincere work is not only an indestructible delight to the worker by its very genuineness, but is immortal in the best sense, for it lives for ever in its influence. There is no good Dictionary, not even a good Index, that is not in this sense priceless, for it has honestly furthered the work of the world, saving labour to others, setting an example to successors.

Source: At Knit's End: Meditations for Women Who Knit Too Much

The Sunborn (2005), Part I, Chapter 4, “Vent R” (p. 38)