The first of these three opinions is excessively rigorous and intrinsically improbable. The Jews had no clearly revealed knowledge of the Trinity and the Incarnation, and consequently were under no obligation to believe them. As the divinely constituted guardians of the Messianic prophecies, they were bound to believe in the Redeemer, though only _necessitate praecepti_. The gentiles were dispensed even from this. The second opinion, which limits the _necessitas medii_ to the New Testament, lacks solid proof. The Scripture texts cited in its support merely prove the efficaciousness of belief in Christ,(805) or the duty of embracing that belief on the strength of the Apostolic preaching,(806) or, finally, the impossibility of redemption except through the mediation of Jesus;(807)—all truths which in themselves have nothing to do with the question under discussion. The third and most probable opinion is that even under the New Covenant, explicit faith in Christ, and _a fortiori_ in the Divine Trinity, cannot be regarded as an indispensable medium of justification and salvation, (1) because St. Paul does not mention these two dogmas in the decisive passage, Heb. XI, 6; and (2) because a supernatural act of justifying love and contrition may be inspired by belief in the existence of God and divine retribution; and (3) because this latter belief implicitly, by way of desire (_fides in voto_), includes belief in Christ and the Trinity.(808) Nevertheless it must be held that an adult who desires to be received into the Church and is baptized in the name of the Most Holy Trinity, is bound to believe in the Trinity and the Incarnation by more than a mere _necessitas praecepti_, namely, by what is technically called _necessitas medii per accidens_, a necessity from which God dispenses only in exceptional cases, when it is either physically or morally impossible to elicit an act of explicit faith.(809) It is for this reason that the Sacred Congregation of the Holy Office decided, February 28, 1703, that missionaries are bound to explain to all adult converts who have the use of reason, even though they be near death, those mysteries of the faith which are necessary for salvation _necessitate medii_, especially the Trinity and the Incarnation.(810) Section 2. The Necessity Of Other Preparatory Acts Besides Faith