Giacomo NACCHIANTI. — Dominican theologian and bishop, born in Florence c. 1500, died in Chioggia on 6 March 1569. He entered the Dominican Order in 1518, and in 1529 was at the Dominican studium generale in Bologna. In 1534 he was magister studentium at the new convent in Perugia; prior at Pisa in 1536 and at Lucca in 1537; in 1541 at Santa Maria sopra Minerva in Rome. He took part in the theological debates that Paul III arranged at his table with the most notable theologians of the city. On 30 January 1544 he was appointed bishop of Chioggia and as such participated in the first phase of the Council of Trent.
His interventions in the conciliar sessions were numerous and at times untimely, as when (5 April 1546) he opposed the wording of the decree on Tradition, which declared that it was to be received «pari pietatis affectu ac reverentia» with the Holy Scriptures. Although he accepted, with exemplary submission, the definitive judgment of the Fathers (session IV, 8 April 1546), from that moment he became suspect, and in 1548, provoked by an accusation from a certain Giulio Ercolano, master of Chioggia, a process was initiated against him, entrusted to Massarelli, secretary of the Council, then transferred to Bologna. Despite the hostility of Massarelli, the process ended favorably for Nacchienti, who reappeared at Trent in the other two phases of the Council, intervening on important questions (the residence of bishops, the sacrificial nature of the Last Supper). Returning to his diocese, he zealously applied the decrees of the Council and celebrated the diocesan synod (31 August 1564).
His numerous works were printed in Venice in 1567 (2nd ed., in 2 vols., Lyons 1657). The principal ones are: *Enarrationes in Ep. ad Ephesios*; *Enarrationes in Ep. ad Romanos*; *Sacrae Scripturae medulla*; *Tractationes XVIII theologales variae*; and brief and concise pamphlets on topics of current interest at the time of the Council of Trent, e.g., *De existentia existendique modo Christi corporis in Sacramento* (op. 1); *De communione Corporis et Sanguinis Christi nobis praecepta* (op. 2); *De summo sacerdotio Christi* (op. 3); *De primatu* (op. 7); *De sacrosanctis indulgentiis* (op. 10); *De Sacramento Matrimonii* (op. 14); *De sacrificio Missae* (op. 15); *Quattuor quaestiones* (creation, immortality of the soul, contingency, infinity of the first mover); *Theorematia theologica, metaphysica, naturalia*.
A follower of St Thomas Aquinas, Nacchienti enriched the master’s doctrine with abundant positive material, presenting the old and the new in a personal synthesis, written in a sober style not lacking in elegance. His works on Scripture are more biblical theology than exegesis, for, following a method already in use in the 15th century (v. , e.g., Favorani), he took his cue from certain themes in the Pauline epistles to gather around them a body of positive data and theological considerations, forming a true treatise; thus, for example, in the *Enarrationes in Ep. ad Romanos* he treats chiefly of justification, and in the *Enarrationes in Ep. ad Ephesios* of the predestination of Christ: here he sets forth and advocates the sceptical theory with that freedom which several 16th-century Thomists, e.g., POLITICA (v.), allowed themselves in the face of the common current. All Nacchienti’s output has the merit of combating Protestantism by opposing to the Lutheran void the riches of Pauline theology, of which he expounds and warmly defends the doctrine of the Mystical Body, insisting on the *subsistentia mystica*.