During his Spanish travels he suffered from bouts of illness and twice returned to England, and in the end his activities were suppressed and he left Spain for Tangier, where the book closes.
[6] The work relates numerous personal encounters Borrow had with Spaniards, from the prime minister to beggars, including Gypsies and crypto-Jews.
[3][7] This was the first widely read book with accurate first-hand information on Gypsies, although a more complete description appears in his first work, The Zincalí (1841), which was not a commercial success.
[6] Borrow's account in the book (Chapters 51–57) of his unscheduled expedition to Gibraltar and Tangier makes it "clear that he was pursuing a private agenda, a dream of discovery about Gypsies, Jews, and Moors.
Borrow's writing style in the book is "effective", conveying "half theatrical and wholly wild exuberance and robustness", even though it "runs at times to rotten Victorianism, both heavy and vague" and shows the influence of Biblical phraseology.
[11] For the historian Raymond Carr (1966), Borrow's "strange masterpiece" is of especial historical value, against the shortage of "orthodox sources" for Spanish history at that period.
[14] The description of Gypsy life in the final chapter of Prosper Mérimée's novella Carmen (the source for Bizet's opera) shows many similarities with those in Borrow's The Bible in Spain and The Zincali.