Ternio sacrorum theorematum, de uno Deo, de uno mediatore, et de Iesu, qui est Christus

The second, drawn from the universal experience of the whole Catholic Church.
None can be the same, or the Head of the Church, giving salvation to the body, that is, preserving all believers of both covenants, except one.
But Jesus Christ is the same today, yesterday, and forever: as the 7th Axiom testifies.

Demonstration leading to the impossible.

If Christ (the word taken kat' exochēn by preeminence, concerning the Prince of life, the holy and just one. Acts 3:14, 15) is not one, then an absurdity follows, namely, that there are many Christs or Princes of life.

But the consequent is absurd and false: as is clear both from the axioms and from those things that follow from this same inconvenience, namely:

1. Not to honor the one Christ the Son, just as they honor the Father: contrary to what the Truth itself pronounced. John 5:23.

2. Not to have one head of the Church, but many: contrary to that oracle of the Holy Spirit. Eph. 5:23, Christ is the head of the Church.

3. Not to have one Mediator between God and men, but several: contrary to the 2nd Axiom.

4. That Christ Jesus was not anointed with the Holy Spirit above his companions: nor is he the perfect JESUS, or Savior, as one who could not have saved his people from their sins without the work of other Christs. Ps. 45:8, John 3:34, Matt. 1:21.

Conclusion.

Wherefore Christ is one in number: which was to be shown.