Throughout his career as a Christian theologian and professor, Dávid learnt the teachings and practices of the Roman Catholic and Magisterial Protestant churches, but later rejected several of them and came to embrace Unitarianism.

[1] Ferenc Dávid was born in Kolozsvár, Hungary (present-day Cluj-Napoca, Romania), to a Transylvanian Saxon father (David Hertel, who worked as a tanner) and to a Hungarian mother.

[3] Gáspár Heltai, the father of Peter's wife Borbála, was a Protestant Reformer, Lutheran and later Unitarian minister, translator, outstanding author of the Hungarian late Renaissance era.

On 1 June 1557 the Diet of Torda (National Assembly) stated that 'everybody should live in a belief that he or she wants if it is done without the distrust of another' which meant for the population of the Principality of Transylvania that it became allowed to practise not just the Roman Catholic, but the Lutheran religion.

After the Battle of Mohács the political instability, the weakening of the Roman Catholic denomination (continuous expansion of the Ottoman Empire, heretic movements in Transylvania especially of Arianism, Bogumilism etc.)

[6][circular reference] A well known Italian antitrinitarian, Giorgio Biandrata moved to Transylvania in 1563 into the royal court of John II Sigismund Zápolya and became his own doctor.

Together with Giorgio Biandrata he published polemical writings against Trinitarian belief, particularly De falsa et vera unius Dei Patris, Filii et Spiritus Sancti cognitione which is largely a summarized version of Servetus's Christianismi Restitutio.

An important difference between the views of the two theologians was that Ferenc Dávid became a nonadorant which meant that he renounced the necessity of invoking Christ in prayers.

Working in the royal court, he convinced the prince about his point of view on religion, so that John II Sigismund Zápolya accepted his theses and became the first Unitarian ruler.

The aim of his life as Ferenc Dávid wrote was 'the restoration of the pure Christianity of Jesus' which meant for him the search for the truth in the whole freedom of thought.

So he sought to persuade the prince, John II Sigismund Zápolya and several people in important positions to reach an agreement between the opposite sides of the religious debate.

[7] In 1571, John II Sigismund Zápolya was succeeded by István Báthory, a Roman Catholic, and the policy shifted toward persecution of the new religious institutions.

When, under the influence of Johannes Sommer, rector of the Gymnasium of Kolozsvár, Dávid denied the necessity of invoking Jesus Christ in prayer (about 1572), the attempted mediation of Faustus Socinus, upon Blandrata's request, was unsuccessful.

After the death of Ferenc David, Lukas Trauzner, his son-in-law, wrote together with Miklós Bogáti Fazekas, Bernard Jacobinus (father of János Jacobinus) and the sons of Ferenc Dávid the Defensio Francisci Davidis in negotio de non invocando Jesu Christo in precibus (Basel, 1581) and were part of the inner opposition of the moderate Unitarianism movement of Demeter Hunyadi.

[11] After the defeat of Mózes Székely started the reign of Giorgio Basta in Kolozsvár who captured the royal judge, Mihály Tótházi and without a sentence beheaded him.

[16] After leaving Calvinism, Dávid adopted the view of Laelio Sozzini that the existence of Christ began when he was conceived by the Virgin Mary through the operation of the Holy Spirit.