I couldn't find any "Sir G. Gostwick" - assuming the G stands for a popular Tudor name like George, Geoffrey, Gilbert, Giles, Gregory, or (more of a long shot) Germain or Gervais.There is however a Sir John Gostwick, who challenged Cranmer in 1544 by announcing in Parliament that the Archbishop professed the Lutheran view of the sacrament. (The King told him to shut up.) Sir John Gostwick is frequently mentioned by historians, since his career and activities are fairly well sourced and reported - he was Wolsey's Master of Horse, and later the Treasurer of the very lucrative Court of First Fruits and Tenths. A.G. Dickens made a particular study of Gostwick, whom he sees as the model of a particular type of Tudor person who benefited from the Dissolution. You can read large parts of Dickens' Reformation Studies (Chapter 19, Estate and Household Management) and The English Reformation online at Google Books - they both discuss Sir John Gostwick in detail.
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