Pietro Vermigli, by Hans Asper, 1560

Peter Martyr Vermigli (1499 – 1562) was an Italian-born Reformed theologian. His early work as a reformer in Catholic Italy and decision to flee for Protestant northern Europe influenced many other Italians to convert and flee as well. In England, he influenced the Edwardian Reformation, including the Eucharistic service of the 1552 Book of Common Prayer. He was considered an authority on the Eucharist among the Reformed churches, and engaged in controversies on the subject by writing treatises. Vermigli's Loci Communes, a compilation of excerpts from his biblical commentaries organized by the topics of systematic theology, became a standard Reformed theological textbook.

Vermigli's best-known theological contribution was defending the Reformed doctrine of the Eucharist against Catholics and Lutherans. Contrary to the Catholic doctrine of transubstantiation, Vermigli did not believe that the bread and wine are changed into Christ's body and blood. He also disagreed with the Lutheran view that Christ's body is ubiquitous and so physically present at the Eucharist. Instead, Vermigli taught that Christ remains in Heaven even though he is offered to those who partake of the Eucharist and received by believers.