Her husband - The word in the original does not imply that they were married. It means here the man to whom she was espoused.
A just man - Justice consists in rendering to every man his own. Yet this is evidently not the character intended to be given here of Joseph. The meaning is that he was kind, tender, merciful; that he was so attached to Mary that he was not willing that she should be exposed to public shame. He sought, therefore, secretly to dissolve the connection, and to restore her to her friends without the punishment commonly inflicted on adultery. The word just has not unfrequently this meaning of mildness, or mercy. See 1 John 1:9; compare Cicero, De Fin. 5, 23.
A public example - To expose her to public shame or infamy. Adultery has always been considered a crime of a very heinous nature. In Egypt, it was punished by cutting off the nose of the adulteress; in Persia, the nose and ears were cut off; in Judea, the punishment was death by stoning, Leviticus 20:10; Ezekiel 16:38, Ezekiel 16:40; John 8:5. This punishment was also inflicted where the person was not married, but betrothed, Deu 21:23-24. In this case, therefore, the regular punishment would have been death in this painful and ignominious manner. Yet Joseph was a religious man - mild and tender; and he was not willing to complain of her to the magistrate, and expose her to death, but sought to avoid the shame, and to put her away privately.
Put her away privily - The law of Moses gave the husband the power of divorce, Deuteronomy 24:1. It was customary in a bill of divorce to specify the causes for which the divorce was made, and witnesses were also present to testify to the divorce. But in this case, it seems, Joseph resolved to put her away without specifying the cause; for he was not willing to make her a public example. This is the meaning here of “privily.” Both to Joseph and Mary this must have been a great trial. Joseph was ardently attached to her, but her character was likely to be ruined, and he deemed it proper to separate her from him. Mary was innocent, but Joseph was not yet satisfied of her innocence. We may learn from this to put our trust in God. He will defend the innocent. Mary was in danger of being exposed to shame. Had she been connected with a cruel, passionate, and violent man, she would have died in disgrace. But God had so ordered it that she was betrothed to a man mild, amiable, and tender: and in due time Joseph was apprised of the truth in the case, and took his faithful and beloved wife to his bosom. Thus, our only aim should be to preserve a conscience void of offence, and God will guard our reputation. We may be assailed by slander; circumstances may be against us; but in due time God will take care to vindicate our character and save us from ruin. See Psalms 37:5-6.