Calvin on Esther

A writer correctly affirmed:

"Luther and Calvin left no commentaries on Esther..."

here

Another writer says:

"John Calvin to never have preached the book."

See here

Another writer, a Reformed writer, wrote:

"As far as we can tell, there were no commentaries written on the book of Esther for the first seven centuries of the Church. And John Calvin, as far as we know, never preached on Esther or wrote a commentary on it. So it seems that people did have a problem with what to make of Esther."

See here

We know Luther rejected the inspiration and canonicity of the Book of Esther. Wrote one author:

"In his correspondence with Erasmus on the issue of free choice, Luther expressed his rejection on the canonicity of Esther. He grouped Esther with Ecclesiasticus, Judith, two books of Esdras (1 Esdras and 2 Esdras), Susanna and (Bel and) Dragon.

The first is that from Ecclesiasticus 15[:14-17]: “God made man from the beginning, and left him in the hand of his own counsel. He added his commandments and precepts. If thou wilt observe the commandments and keep acceptable fidelity forever, they shall preserve thee. He hath set water and fire before thee; stretch forth thine hand for which thou wilt. Before man is life and death, good and evil; that which he shall choose shall be given him.” Although I could rightly reject this book, for the time being I accept it so as not to waste time by getting involved in a dispute about the books received in the Hebrew canon. For you [Erasmus] poke more than a little sarcastic fun at this when you compare Proverbs and The Song of Solomon (which with a sneering innuendo you call the “Love Song”) with the two books of Esdras, Judith, the story of Susanna and the Dragon, and Esther (which despite their inclusion of it in the canon deserves more than all the rest in my judgment to be regarded as noncanonical)."  (Luther’s Works, Vol. 33, page 110)

"In one of his Table Talk, Luther was reported of saying: ‘I hate Esther and 2 Maccabees so much that I wish they did not exist; they contain too much Judaism and no little heathen vice." (quoted from F.F. Bruce: The Canon of Scripture, page 101)."

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The French Confession of 1559 lists the book of Esther. This confession was not objected to by Calvin. It appears that Calvin had his doubts about the book, but did not feel that it was an issue that demanded his thunderous writings.