From Jack Kerouac's *On the Road*

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> Through halos and rolls and gold foals that were like the existence of the gleaming spear in His right hand which sayeth c’mon boy, **go thou** across the ground. Go moan for man. Go moan. Go groan. Go groan alone. Go roll your bones. Alone. **Go thou** and be little beneath my sight. **Go thou** and be minutest seed in the pod. **Go thou go thou** – die hence, and if this world report you well and truly.
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It can be inferred from the text that Kerouac probably uses it to mean "Go!" but where did it come form?