Jerome, Saint. [Letter to Eustochium, 408-410] in Commentariorum in Esaiam 73: 1-4, 41, 83, 128, 159, 223, 266, 315, 354, 336-37, 427-28. 73a: 465-66, 506-07, 552, 598-99, 641-43, 691-92, 740-42

[Letter from Saint Jerome to Eustochium]
Jerome writes the long (18 books) commentary on Isaiah which he had originally promised Paula and which Eustochium has pressed him to do. He continues to address Eustochium directly throughout the work, in prologues to the individual books, where he talks about the historical or literal and allegorical (anagogic and tropological) senses, excuses the necessary length and detail of his exposition, which he knows will not appeal to Roman tastes, and lashes out at his detractors. He also defends himself for writing to women, and makes a discovery about the text in answer to a difficult question from Eustochium. In the later books, he is painfully aware of his mortality.
Online at Epistolae (See also Bibliographia record).