From: Matthew 13:54-58
No One is a Prophet in His Own Country
 And coming to His (Jesus') own country He taught them in their synagogue, so that they were astonished, and said, "Where did this Man get this wisdom and these mighty works?  Is this not the carpenter's son? Is not His mother called Mary? And are not His brethren James and Joseph and Simon and Judas?  And are not all His sisters with us? Where then did this Man get all this?"  And they took offense at Him. But Jesus said to them, "A prophet is not without honor except in his own country and in his own house."  And He did not do many mighty works there, because of their unbelief.
53-58. The Nazarenes' surprise is partly due to people's difficulty in recognizing anything exceptional and supernatural in those with whom they have been on familiar terms. Hence the saying, "No one is a prophet in his own country." These old neighbors were also jealous of Jesus. Where did He acquire this wisdom? Why Him rather than us? They were unaware of the mystery of Jesus' conception; surprise and jealousy cause them to be shocked, to look down on Jesus and not to believe in Him: "He came to His own home, and His own people received Him not" (John 1:11).
"The carpenter's son": this is the only reference in the Gospel to St. Joseph's occupation (in Mark 6:3 Jesus Himself is described as a "carpenter"). Probably in a town like Nazareth the carpenter was a general tradesman who could turn his hand to jobs ranging from metalwork to making furniture or agricultural implements.
For an explanation of Jesus' "brethren", see the note on Matthew 12:46-47.
[The note of Matthew 12:46-47 states:
46-47. "Brethren": ancient Hebrew, Aramaic and other languages had no special words for different degrees of relationship, such as are found in more modern languages. In general, all those belonging to the same family, clan and even tribe were "brethren".
In the particular case we have here, we should bear in mind that Jesus had different kinds of relatives, in two groups--some on His mother's side, others on St. Joseph's. Matthew 13:55-56 mentions, as living in Nazareth, James, Joseph, Simon and Judas ("His brethren") and elsewhere there is reference to Jesus' "sisters" (cf. Matthew 6:3). But in Matthew 27:56 we are told that James and Joseph were sons of a Mary distinct from the Blessed Virgin, and that Simon and Judas were not brothers of James and Joseph, but seemingly children of a brother of St. Joseph.
Jesus, on the other hand, was known to everyone as "the son of Mary" (Mark 6:3) or "the carpenter's son" (Matthew 13:55).
The Church has always maintained as absolutely certain that Jesus had no brothers or sisters in the full meaning of the term: it is a dogma that Mary was ever-Virgin (cf. note on Matthew 1:25).]
Source: "The Navarre Bible: Text and Commentaries". Biblical text taken from the Revised Standard Version and New Vulgate. Commentaries made by members of the Faculty of Theology of the University of Navarre, Spain. Published by Four Courts Press, Kill Lane, Blackrock, Co. Dublin, Ireland. Reprinted with permission from Four Courts Press and Scepter Publishers, the U.S. publisher.