Divine Veracity, Revelation, and Motives of Credibility

The evidential use of miracle presupposes the truthfulness of God. Catholic theology therefore joins the ontology of divine action to an epistemology of revelation and faith.

Vatican I supplies Catholicism’s mature formal account of what miracles can establish as motives of credibility.

Vatican I rejects both rationalism and fideism.

Faith is not produced because the mysteries of Christianity become intrinsically demonstrable by natural reason. We believe ultimately because of the authority of God revealing, who neither deceives nor can be deceived.

But God also wills faith to be reasonable rather than blind. Consequently, God joins the inward assistance of grace to outward evidence, especially miracles and prophecy. The Catechism, directly repeating Vatican I, calls these motives of credibility, motiva credibilitatis.

This is a critical distinction:

formal motive of faith: God revealing.

rational grounds for recognizing revelation as credible: miracles, prophecy, Christ, apostolic testimony, holiness, historical continuity, the Church herself, and so forth.

Miracles therefore do not prove the Trinity in the manner geometry proves a theorem.

Rather, they can rationally support:

This claimant really has been divinely accredited. Therefore I have sufficient reason to receive from him truths that surpass what I could discover by natural reason alone.

That is the Catholic epistemology.

And because grace still moves the will and intellect, faith is neither a blind leap nor an involuntary conclusion forced on the mind by laboratory demonstration.

A technical point in Chapter IV should be preserved whenever Lambertini is cited.

He acknowledges a scholastic question about what God might do under some hypothetically different providential order. Rather than solve the entire issue of absolute divine power, Lambertini says it is sufficient for his purposes that under the present providential order, according to God's ordinary power, a true miracle cannot be given for confirmation of false doctrine or false sanctity.

So a very exact scholarly formulation would be:

Lambertini's canonical thesis concerns the providential economy God has actually established, not an unrestricted speculation about every logically conceivable divine ordering.

Then he strengthens the practical conclusion from divine veracity. God is Truth and cannot become witness to falsehood.

That nuance matters because it keeps us from turning a carefully framed scholastic discussion into a simplistic modal slogan.

Another fascinating passage concerns the hypothetical of an angel preaching another Gospel or an impossible counter-sign apparently contradicting established Christian revelation.

Lambertini treats such a situation as a hypothetical condition that cannot actually be realized as genuine divine testimony. Were one confronted with an apparent sign against Catholic truth, the standard of judgment would remain the prophetic and apostolic teaching and the Church's received tradition, because the alleged counter-sign could not at the same time constitute infallible divine testimony.

This produces a hierarchy:

God's truthful revelation interprets signs; signs do not constitute an autonomous oracle capable of making God contradict himself.

That is extremely important for the question of whether an apparent miracle could contradict Catholic dogma:

Could a miracle disprove Catholic dogma?

Lambertini's answer is not “ignore evidence.” It is more conceptually precise:

if the phenomenon genuinely signifies contradiction of revealed truth, then at least one component of the proposed analysis is wrong: its causal attribution, miraculous status, or supposed signification.

The contradiction prevents both sides from being simultaneously divine testimony.

Lambertini is careful about modality. For his canonical purposes, it is enough to maintain that in the providential economy actually established by God, a true miracle cannot be ordered to the confirmation of false doctrine or false sanctity. The claim is not an attempt to map every abstract possibility under divine absolute power.

Vatican I then situates miracles among the external motives of credibility. Faith remains supernatural because its formal motive is the authority of God revealing; miracles do not replace that motive. They can, however, give public rational grounds for recognizing a purported revelation as credible rather than as a blind impulse.

Lambertini, De Servorum Dei IV.1, ch. IV, pp. 42–45; Vatican I, Dei Filius, ch. 3; CCC §156.