Ferrazzi was born at Cartigliano (Vicenza) in 1813. Having entered the seminary at an early age, he took his vows in 1835. He taught humanities, geography and history at the upper school in Bassano del Grappa. He was a refined speaker and an unoriginal poet, copying the style of Zaccaria Bricito and Giuseppe Barbieri, and was a member of the Ateneo Veneto and the Accademia dei Concordi of Rovigo. Through the establishment of the Ateneo di scienze, lettere ed arti he enlivened the culture of Bassano del Grappa and edited a collection of studies on the town and its most celebrated citizens.

He was a fervent patriot (his Library was closed down because of his stance against the Austrians) and in 1848 he urged the citizens of Bassano to take up arms. As a result, he was soon forced to go into hiding and was later forbidden to teach, if only for a few months. The sanctions he suffered had not quenched his patriotic fervour, and his writings continued to reveal his idea of a scientific and humanistic culture seen as the life-blood of a nation, unified also by a language made great by the literary achievements of the glorious writers of the nation, with Dante at its head. All this did not escape the attention of the authorities and cost him a two-year ban from preaching. When Veneto too became part of Italy, Ferrazzi, who had by then reached the retirement age for a teacher, dedicated himself vigorously to the Ateneo di scienze, lettere ed arti, making it a centre for study and the promotion of culture aimed at the uneducated in society.

He was briefly involved in politics as a local councillor and mayor of Cartigliano, but the post he found more suited to his personality was as a schools inspector, which he carried out with passion for many years among the teachers and the pupils of the area around Bassano. He firmly believed in popular education as the only antidote to political subjugation. Although he never left the sleepy provinces, he forged links with some of the major intellectuals of his time through a frequent exchange of letters. He was interested in local history and culture, was involved with journalism and published school textbooks, without neglecting entirely some attempts at poetry.

He produced various bibliographical works on the major Italian poets (Dante, Petrarch, Ariosto, Tasso). But, above all, it was the five volumes of his Manuale dantesco that represent the fruits of his collection of miscellaneous information and documents over decades. Dante studies were the main subject of his brief correspondence with Raffaello Caverni, who was encouraged by Ferrazzi to publish his Problemi di astronomia dantesca and his small dictionary Voci e modi nella Divina Commedia dell’uso popolare toscano. Ferrazzi died in Bassano del Grappa in 1887, leaving his library to the town.