a term used to refer to various notions of the essence of God or Divinity. Godhead in Judaism, is the unknowable aspect of God, beyond all actions or emanations. Godhead in Christianity is also the Divine Nature or Substance of God, but in most of its sects, emphasis is placed upon it as the Unity of three persons of the Trinity: God the Father, Christ the Son, and the Holy Spirit. The word has been widely used to translate the Hindu word Brahman, and sometimes used to present concepts of Atman, Vishnu, Shiva and Shakti.
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The doctrine that God could have a son, or that there could be more than one person in the Godhead, was to him profanity, infidelity, and downright blasphemy.
Kersey and Lydia Graves. The Bible of Bibles (1879)
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Nothing could hide the tiredness of their spirit and their flesh; time had eroded their godhead.