Martin Seidelius was a Polish Unitarian

Unitarianism

Unitarianism is a Christian theological movement, named for its understanding of God as one person, in direct contrast to Trinitarianism which defines God as three persons coexisting consubstantially as one in being....

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Martin Seidel was a refugee from Oława in Silesia, who sided with the Szekler Sabbatarians

Szekler Sabbatarians

The Szekler Sabbatarians were a religious group in Transylvania and Hungary between the Sixteenth and Nineteenth centuries who held Unitarian and judaizing beliefs.-History:The Magyar...

 of the Unitarian movement in Transylvania

Transylvania

Transylvania is a historical region in the central part of Romania. Bounded on the east and south by the Carpathian mountain range, historical Transylvania extended in the west to the Apuseni Mountains; however, the term sometimes encompasses not only Transylvania proper, but also the historical...

, which Sozzini characterised as "semi-judaizers". Seidel rejected the Messianic doctrine of the New Testament. In 1611 he published Miscellanea; hoc est, Scripta theologica seu. tractatus breves de vidersis with Jan Niemojewski

Jan Niemojewski

Janusz Jan Niemojewski was a Polish nobleman, and theologian of the Polish Brethren.-Works:* 1583 - "Odpowiedź na potwarz Wilkowskiego"* 1583 - "Obrona przeciw niesprawiedliwemu obwinieniu"....

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In 1618 he recorded the debate on worship of Christ between Fausto Sozzini and Christian Francken

Christian Francken

Christian Francken was a former Jesuit who became an anti-Trinitarian writer.In 1577 Francken left his position as professor of the Jesuit college in Vienna and commenced the publication from Basel and La Rochelle of many tracts against the order.François Du Jon in 1584 wrote his Defensio...

. Disputatio de adoratione Christi, habita inter F. Socinum & C. Francken (246 pages)

His Origo et Fundamenta de Religione Christianae (post.1680) shows a deist position.