Unitarian preacher, writer, and theologian influential in promoting religious toleration and the growth of anti-Trinitarian thought in Hungary.

After successively rejecting Roman Catholicism and Lutheranism, in 1566 Dávid became bishop of the Calvinist community at Kolozsvár and court preacher to the Unitarian king John Sigismund. Converted to Unitarianism by the Italian physician Georgius Blandrata (Blandrata, George) before 1567, Dávid began to advocate the unity rather than the trinity of the Godhead. He transformed the Great Church at Kolozsvár into a centre of anti-Trinitarianism, introduced Unitarianism at the court, secured state toleration from the Transylvanian Diet through the Edict of Torda (1568), and won many converts.

About 1571, however, when the Catholic Stephen Báthory acceded upon the death of Sigismund and initiated persecutions of Unitarians, Dávid began to advocate the view that Christ should not be worshipped at all. This attitude conflicted with the teachings of Blandrata, who allied himself with Báthory and tried, with the Unitarian theologian Faustus Socinus, to influence Dávid to moderate his position. All reconciliation efforts failed, and Dávid's supporters separated themselves from the movement as Dávidists, or Old Unitarians, in opposition to Blandrata's New Unitarian faction.

Dávid, whose followers were also known as Nonadorantes, was charged with introducing Judaizing tendencies, partly because his refusal to accord adoration to Christ resembled the rejection by Judaism of Christ as a Messiah. In 1579 Dávid was brought to trial as a blasphemous innovator and condemned to life in prison, where he died that same year. The worship of Christ in Unitarian churches remained an established practice until the 19th century.

Among Dávid's many writings in Latin and Hungarian are sermons; catechisms; four theses opposing the invocation of Christ in prayer, De non invocando Jesu Christo in precibus sacris; and the important anti-Trinitarian work De falsa et vera unius Dei Patris, Filii et Spiritus Sancti (1567; “On the False and True Unity of God the Father, Son, and Holy Ghost”).