The simple answer is that we do not have any record of St. Joseph’s age when he was betrothed to our Blessed Mother Mary and when Christ was born. Indeed, the portrayal of St. Joseph also is conflicting. For example, Guido Reni’s “St. Joseph and the Child” depicts a gray-haired elderly man holding baby Jesus, whereas Jose de Ribera’s “St. Joseph and the Boy Jesus” and Bartolome Murillo’s “The Holy Family” depict a young man with the child Jesus.
The depiction of St. Joseph as an elderly man arises from a “speculation” in the Eastern churches that he was an elderly widower who had other children before he married Mary. This speculation sought to solve two issues:
First, Mary is the ever-virgin mother of our Savior, and therefore, she and St. Joseph did not have other children. Unlike a virile young man, an old man past his prime would not be tempted to have conjugal relations with a much younger woman. Surely his libido would have quelled long ago. In this sense, an old St. Joseph is “a safe St. Joseph.”
Second, the elderly widower St. Joseph who had other children would explain the Gospel references to “the brothers and sisters of the Lord.” These brothers and sisters would really then be Jesus’ half-brothers and half-sisters, but only by law, not by blood since Joseph was not the natural father of Our Lord. For example, in the Gospel of St. Mark, we read, “Isn’t this the carpenter, the son of Mary, a brother of James and Joses and Judas and Simon? Aren’t his sisters our neighbors here?” (Mk 6:3).
The “elderly widower” argument is not needed if one understands the meaning of brother.
In the original text of the Gospel, the Greek word “adelphos”, meaning “brother,” is used. However, adelphos does not just mean a blood brother born of the same parents but also a half-brother, a step-brother or even another male relationship, like a cousin or a nephew. Note also that in Hebrew and Aramaic, no special word existed for cousin, nephew, half-brother or step-brother; so they used the word “brother” or a circumlocution, such as in the case of a cousin, “the son of the brother of my father.”
The same understanding is true for the word sister. For example, in the Gospel, Mary of Clopas is called “the sister” of Mary, the Mother of Jesus. Obviously, St. Ann and St. Joachim would not have named two daughters “Mary”; instead, the “sister” used here denotes a cousin relationship.
Also, regarding the citation from the Gospel of St. Mark, other gospel passages clarify the relationships between Jesus and James, Joses, Judas and Simon. Note that the James here is James the Less, the bishop of Jerusalem. James the Less and Joses were the sons of Mary the wife of Clopas (Mk 15:40, Jn 19:25), and James the Less was specifically identified as “the son of Alphaeus” (Lk 6:15); here “Clopas” and “Alphaeus” are names traditionally said to identify the same man, just as “Jude” and “Thaddeus” refer to the same apostle, i.e., St. Jude Thaddeus. Judas, and by extension Simon, were the sons of James (not either of the apostles) (Lk 6:16). James the Greater and John were the sons of Zebedee with a mother other than our Blessed Mother Mary (Mt 20:20 ff). In sum, there is no need to think that St. Joseph had to be an elderly widower to resolve the supposed brother/sister relationship question.
Also, I personally cannot imagine an elderly St. Joseph walking 100 miles from Nazareth to Bethlehem to register for the census, or walking from Bethlehem to Egypt to flee the wrath of King Herod. I also happily imagine St. Joseph as the young man who could provide for his family and also as the good masculine example and image of human fatherhood for Jesus. Archbishop Fulton Sheen, in his book The World’s First Love, posited: “Joseph was probably a young man, strong, virile, athletic, handsome, chaste, and disciplined, the kind of man one sees … working at a carpenter’s bench. Instead of being a man incapable of loving, he must have been on fire with love. … Young girls in those days, like Mary, took vows to love God uniquely, and so did young men, of whom Joseph was one so preeminent as to be called the ‘just.’ Instead then of being dried fruit to be served on the table of the King, he was rather a blossom filled with promise and power. He was not in the evening of life, but in its morning, bubbling over with energy, strength, and controlled passion” (pp. 77-78).
Granted, while no record exists of St. Joseph’s actual age, the image of a young virile St. Joseph best captures the words of the litany in his honor: “St. Joseph – chaste guardian of the Virgin, foster father of the Son of God, diligent protector of Christ, head of the Holy Family, most just, most chaste, most prudent, most strong, most obedient, most faithful. …” In an age where fatherhood has been marginalized, masculinity undermined and chastity scorned, may each of us honor and cherish the example of St. Joseph, trusting in his prayers to help us on the path of salvation.