Laborare est orare. By the Puritan moralist the ancient maxim is repeated with a new and intenser significance. The labor which he idealizes is not simply a requirement imposed by nature, or a punishment for the sin of Adam. It is itself a kind of ascetic discipline, more rigorous than that demanded of any order of mendicants — a discipline imposed by the will of God, and to be undergone, not in solitude, but in the punctual discharge of secular duties. It is not merely an economic means, to be laid aside when physical needs have been satisfied. It is a spiritual end, for in it alone can the soul find health, and it must be continued as an ethical duty long after it has ceased to be a material necessity.

R. H. Tawney (1880-1962) English writer, economist, historian, social critic [Richard Henry Tawney]

Religion and the Rise of Capitalism, ch. 4 (1926)
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The Latin means, "To work is to pray."