If you were God the Father sending your Only Begotten Son to become human within the Immaculate Womb of Mary whom you prepared by her Immaculate Conception, would you entrust these two treasures of yours to any man? Or would you prepare a man from his beginning to be a proper husband and father to your greatest treasures? The answer is obvious.
We know very little about Joseph's preparation. In fact, we only see the fruits of his preparation. But by these fruits, we can draw some conclusions.
Joseph is "of the house of David." [Luke 1:27] While we often overlook this, the Messiah was promised to be a descendant of David. So, there was much preparation needed. Joseph needed the correct heritage in order to pass it on to Jesus. Remember, this is about Jesus. Joseph is someone with a great and unique relationship with Jesus in order for us to get closer to Jesus.
Joseph is also "a just man." ('righteous' in some translations) [Matthew 1:19] To us this sounds like Joseph is a good man, but this means much more. To be called just, or righteous, at the time of Jesus was the ultimate compliment of holiness. It would be akin to us calling someone 'a walking saint.' And most, if not all, of those we have seen or heard of as 'walking saints' were different, in a good way, when they were younger. And yet, none of them were given the responsibilities Joseph was. So, Joseph's preparation must have started very early and been quite extraordinary.
Fathers receive most of their preparation by being children. Their father gives them an example and indeed fathers leave a spark of their fatherhood in their sons. So if Joseph was prepared so early by the Heavenly Father AND Joseph was a good son to Him AND Joseph was to be the virginal father of the Only Begotten Son of the Father, surely we can say that the Heavenly Father gave to Joseph a spark of His Divine Fatherhood. WOW! Such a tremendous gift for a tremendous responsibility.
Joseph, you were prepared richly for your great responsibility. As you were prepared to be our father as well, fulfill your fatherly responsibilities towards us and bless all fathers to fulfill their fatherly responsibilities as well. Amen.