How did Eutyches explain the relationship between Christ's humanity and divinity?

Eutyches, a 5th-century archimandrite, proposed a Christological doctrine that emphasized the exclusive prevalence of Christ's divinity following the Incarnation. His teaching is summarized by his formula, "two natures before, one after the incarnation," which asserted that upon the union of the divine and human, Christ's human nature was deified and subsumed into a single, divine essence.1

Consequently, Eutyches argued that the humanity of the incarnate Christ was not of the same substance as that of other human beings. This position, known as Eutychianism, was an extreme form of monophysitism that denied the two natures of Christ—divine and human—that were later formally established as orthodox doctrine at the Council of Chalcedon in 451. Because his teaching effectively eliminated the distinct human nature of Christ, it was condemned as heretical by the church.213