I was about to say this in another discussion somewhere else, and wondered: do we know that? As in "it's mentioned or at least hinted at in $book $chapter:$verse"?
Or is it just a very likely conjecture?
A discussion here talks about the various possibilities. To quote a small part that summarizes well:
This page from the same site offers additional explanation for the stonemason theory:
The above quoted site is provided by That the World May Know Ministries, and offers a DVD series entitled Faith Lessons, featuring the founder Ray Vander Laan which offers documentary-style on-location Bible studies suitable for small groups. I believe the one that addresses this issue is Life and Ministry of the Messiah, or possibly Walk as Jesus Walked. It has been several years since I've watched these, and I don't have access to them now to confirm.
We know that Joseph was a τέκτων (tekton)- traditionally a carpenter but literally, any craftsman who worked with his hands, from Matthew 13:55 (Is this not the carpenter's son?). Traditionally, boys would follow in their father's occupation, hence the tradition that Jesus was a carpenter.
Additionally in Mark 6:3, we get the same word describing Jesus himself. (Is this not the carpenter?). Mark is probably the older source ( the Farrer hypothesis ) from which Matthew is drawing. With Matthew's desire to portray Jesus as king, it makes sense that he would prefer to move such a menial task to the dad and let people just assume that Jesus would have been trained up in the family trade.
Yes, Jesus is called a carpenter in Mark 6:3 NIV1984:
Update: based on comments below, some explanation of the word carpenter. First, that is the word used in various translations, e.g. Amplified, Good News, New American Standard Bible and King James. Secondly, it is true that the meaning has been questioned in some commentaries, where it has been suggested that the word could also mean, craftsman. So, we cannot be 100% sure, but since the church has historically considered Jesus to have been a carpenter, and most or all translations use that, it seems probable.
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