How old was St. Joseph when he married the Blessed Virgin Mary? According to the Church Fathers or other Catholic theologians, how old was St. Joseph when he married the Blessed Virgin Mary?
According to ch. 1 of The Divine Favors Granted to St. Joseph (1973) by Père Binet, S.J., the general opinion among theologians is that St. Joseph was, when he married, &quot;neither an old man nor a youth, but in the prime of life, between thirty and forty&quot;:

A secret inspiration from heaven caused both Mary and Joseph to contract this alliance, while adoring in their hearts the impenetrable counsel of the great God. Mary was in her fifteenth year; the age of Joseph is not known so exactly, tradition being silent on the subject. The opinion that he was about eighty years old is without reasonable grounds, and is not held by theologians, the most esteemed of whom think that he was neither an old man nor a youth, but in the prime of life, between thirty and forty. There are many reasons in support of this opinion, which is now generally held.


The first treatise on St. Joseph, the 1522 Summa de donis de S. Joseph by Isidore de Isolanis, O.P. (pp. 81-88, PDF pp. 110-17), advances several arguments:
in favor of a young St. Joseph

Spouses were roughly the same age. St. Mary was younger. ∴, St. Joseph was young.
St. Mary couldn't be thought to be St. Joseph's daughter.
St. Joseph needed to be young and healthy to protect St. Mary and Jesus, travel to different regions, and work for them.
The prophecy Isaiah 62:5: &quot;For the young man [St. Joseph] shall dwell with the virgin [St. Mary]&quot;

opposed to a young St. Joseph

He was middle-aged, but old enough to be manly and knowledgeable of Holy Scriptures.
He must have been old enough to have acquired a grave demeanor, prudence, and fortitude.
He stayed 7 years in Egypt. The Egyptians hated the Israelites, so he must have been old enough to defend against this.