A person who believes in or teaches the doctrine of consubstantialism.
From 'consubstantialism' + '-ist' (one who practices or believes). The '-ist' suffix, from Latin and Greek, turns an abstract belief system into a label for a person who holds that belief.
Medieval and Reformation theologians were basically the academic superstars of their time, and being called a 'consubstantialist' could get you in serious trouble with the church—this word represents centuries of religious arguments that literally divided countries.
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