Latin is the official language traditionally associated with the inscriptions and liturgical setting of the Sistine Chapel’s fresco program. Latin was the principal language of the Roman Catholic Church’s Western tradition during the chapel’s Renaissance decoration.
The paintings themselves communicate through images rather than depending on long written captions. Their subjects come primarily from the Bible and Christian tradition, while the chapel’s ceremonies and papal functions historically used Latin extensively.
Italian is an important language for discussing the artists, commissions, and later scholarship, but it was not the formal liturgical language that defined the chapel’s papal context. Greek and Hebrew also appear in Christian and biblical studies, yet they are not the chapel’s traditional official language.
The language question is therefore about the chapel’s institutional and liturgical identity, not about the language spoken by every artist or visitor who entered the building.