Q. We don’t hear much about Joseph in the Bible. Do we know how old he was when Mary and he married? How old was he when he died, how did he die, and how old was Jesus when he died?
We don’t have exact answers to any of these questions because, as you say, we don’t hear much about Joseph in the Bible.
We do know that in New Testament times, Jewish women often married in their mid-teens, while Jewish men married when they were a bit older, perhaps around twenty, once they had become somewhat established and could support a wife. So if Joseph and Mary’s experience was typical for the period, he might have been just out of his teens when he married her, and she was likely still a teenager.
We know from the gospels that Joseph was at least still alive when Jesus was twelve years old. Luke tells us how Joseph and Mary brought Jesus to Jerusalem at that age, where he spoke with the teachers of the law in the temple. But Joseph seems to have died by the time Jesus was 30 and began his ministry. The gospels portray Jesus interacting with his mother and brothers at several points during his ministry, but never with Joseph.
We know nothing about how Joseph died, or how old he was when he died, except that if he married at around age 20, and had died by the time Jesus was 30, then he would like have died before age 50. So he would have lived a little shorter time than the average for a man in the Roman Empire, which was the mid-50s. But whether he died of illness or an accident or some other cause, we just don’t know.
So the primary picture we have of Joseph comes from the time around the birth of Jesus. What stays in our minds is that he was a righteous man, unwilling for Mary to experience public disgrace, and that he accepted the challenging role of being the adoptive earthly father of the Son of God. Perhaps it’s best that we think of him mostly in that light.