Now perhaps might be a good time to review the basics of orthodox Trinitarianism. To do so, we will use the second chapter of Girolamo Zanchi’s 1586 work De religione Christiana fides (A Confession of Faith concerning the Christian Religion) 1 as a brief summa of the classical doctrine of the Holy Trinity. The chapter, De Deo, divinisque personis et proprietatibus (“On God, and on the Divine Persons and Properties”), has seven sections, so this post is the first in a series of seven.
I. Unum tantum esse Deum, in tres personas distinctam.
Edocti igitur a Deo in Sacris literis, quae sunt ipsius verbum, credimus, unum tantum esse Deum, hoc est, unam simplicissimam, impartibilem, aeternam, viventem, perfectissimamque essentiam in tribus ὑφισταμένοις, seu (ut Ecclesia solita est loqui) personis, aeterno nimirum Patre, aeterno Filio, aeterno Spiritu sancto, inter se vere, sed citra omnem divisionem, distinctis, subsistentem: principium et causam rerum omnium.
I. That there is only one God, distinguished in[to] three persons.
Therefore, having been taught by God in the sacred writings, which are his Word, we believe that there is only one God, that is, one most simple, indivisible, eternal, living, and most perfect essence, subsisting in three hypostases, or (as the Church is accustomed to speak) persons, namely, the eternal Father, the eternal Son, the eternal Holy Spirit, distinguished among themselves truly, but apart from all division: the principle and cause of all things. 2