Apollinarism or Apollinarianism was a view proposed by Apollinaris of Laodicea (died 390) that Jesus had a human body and lower soul (the seat of the emotions) but a divine mind. Apollinaris further taught that the souls of men were propagated by other souls, as well as their bodies. The Trinity had been recognized at the Council of Nicea in 325, but debate about exactly what it meant continued. A rival to the more common belief that Jesus Christ had two natures was monophysitism ("one nature"), the doctrine that Christ had only one nature. Apollinarism and Eutychianism were two forms of monophysitism.

Theodoret charged Apollinaris with confounding the persons of the Godhead, and with giving into the heretical ways of Sabellius. Basil accused him of abandoning the literal sense of the scripture, and taking up wholly with the allegorical sense. His views were condemned in a Synod at Alexandria, under Athanasius of Alexandria, in 362, and later subdivided into several different heresies, the main ones of which were the Polemians and the Antidicomarianites.

It was declared to be a heresy in 381 by the First Council of Constantinople, since Christ was officially depicted as fully human and fully God. Followers of Apollinarianism were accused of attempting to create a tertium quid ("third thing," neither God nor man).

References

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• Catholic Encyclopedia entry