Harold, the Last of the Saxon Kings Book X: The Sacrifice on the Altar by Edward Bulwer-lytton

It is the nature of that happiness which we derive from our affections to be calm; its immense influence upon our outward life is not known till it is troubled or withdrawn. By placing his heart at peace, man leaves vent to his energies and passions, and permits their current to flow towards the aims and objects which interest labour or arouse ambition. Thus absorbed in the occupation without, he is lulled into a certain forgetfulness of the value of that internal repose which gives health and vigour to the faculties he employs abroad. But once mar this scarce felt, almost invisible harmony, and the discord extends to the remotest chords of our active being. Say to the busiest man whom thou seest in mart, camp, or senate, who seems to thee all intent upon his worldly schemes, "Thy home is reft from thee -- thy household gods are shattered -- that sweet noiseless content in the regular mechanism of the springs, which set the large wheels of thy soul into movement, is thine nevermore!"

-- and straightway all exertion seems robbed of its object -- all aim of its alluring charm. "Othello's occupation is gone! " With a start, that man will awaken from the sunlit visions of noontide ambition, and exclaim in his desolation anguish, "What are all the rewards to my labour now thou hast robbed me of repose? How little are all the gains wrung from strife, in a world of rivals and foes, compared to the smile whose sweetness I knew not till it was lost; and the sense of security from mortal ill which I took from the trust and sympathy of love?"