St. Joseph, Righteous Man

This is taken from Commentary of St Mathew by Scott Hahn. I  (Rev. Julio Penacoba) find it very interesting and for me even quite consoling to know about who support the third theory.

1:19 just: Or, "righteous". Joseph is a man of sterling moral character, committed to living by the Mosaic Law (Deut 6:25; Lk 1:6). put her to shame: The Greek verb does not necessarily have a negative connotation. It simply means "to expose" or "to exhibit". send her away: Catholic tradition proposes three main interpretations to explain why Joseph resolved to end his betrothal with Mary. (1) The Suspicion Theory. Some hold that Joseph suspected Mary of adultery when he discovered her pregnancy. Joseph thus intended to pursue a divorce in accord with Deut 24:1-4 until the angel revealed to him the miraculous cause of the conception (1:20). Joseph is said to be righteous because he shuns immorality and directs his life by the Law of God. Proponents of this view include St. Justin Martyr,St. John Chrysostom, and St. Augustine. (2) The Perplexity Theory. Others hold that Joseph found the situation of Mary's pregnancy inexplicable. Divorce seemed to be his only option, and yet he wished to do this quietly, for he could not bring himself to believe that Mary had been unfaithful. Joseph is said to be righteous because he lives by the Law of God and judges Mary's situation with the utmost charity. The main proponent of this view is St. Jerome, whose exegesis was adopted into the notes of the medieval Bible. (3) The Reverence Theory. Still others hold that Joseph knew the miraculous cause of Mary's pregnancy from the beginning, i.e., he was made aware that the child was conceived "of the Holy Spirit" (1:18). Faced with this, Joseph considered himself unworthy to be involved in the Lord's work, and his decision to separate quietly from Mary was a discretionary measure to keep secret the mystery within her. On this reading, the angel confirms what Joseph had already known and urges him to set aside pious fears that would lead him away from his vocation to be the legal father of the Messiah (1:20). Joseph is said to be righteous because of his deep humility and reverence for the miraculous works of God. Proponents of this view include St. Bernard of Clairvaux and St. Thomas Aquinas.