“Whatever good fortune befalls you, attribute it to the gods.”

"Sailing Ships", p. 162
Collected Poems (1933)
Context: While many a lovely ship below sailed by
On unknown errand, kempt and leisurely;
And after each, oh, after each, my heart
Fled forth, as, watching from the Downs apart,
I shared with ships good joys and fortunes wide
That might befall their beauty and their pride…

The Varieties of Scientific Experience: A Personal View of the Search for God (2006)

Variant translation: Success is man's god.
Source: Oresteia (458 BC), The Libation Bearers, line 59

Source: Meditations

Book Two, Part I “In the Wilderness”, Chapter 2 (p. 240)
Quest for the White Witch (1978)

Part I, Prop. XXIX, Scholium (trans: Edwin Curley, London: Penguin, 1996)
Ethics (1677)

Hays translation
V, 37
Meditations (c. AD 121–180), Book V

Kleomenes, sec. 22
Parallel Lives

IX. On Providence, Fate, and Fortune.
On the Gods and the Cosmos
Context: To believe that human things, especially their material constitution, are ordered not only by celestial beings but by the celestial bodies is a reasonable and true belief. Reason shows that health and sickness, good fortune and bad fortune, arise according to our deserts from that source. But to attribute men's acts of injustice and lust to fate, is to make ourselves good and the Gods bad. Unless by chance a man meant by such a statement that in general all things are for the good of the world and for those who are in a natural state, but that bad education or weakness of nature changes the goods of Fate for the worse. Just as it happens that the Sun, which is good for all, may be injurious to persons with ophthalmia or fever.