John Gill Commentary Mark 6:4

"And Jesus said unto them, A prophet is not without honor, save in his own country, and among his own kin, and in his own house." — Mark 6:4 (ASV)

But Jesus said unto them
The following proverb;

a prophet is not without honour, but in his own country, and among
his own kin, and in his own house ;
the same as in (Matthew 13:57) ; (See Gill on Matthew 13:57). Only the phrase, "among his own kin", is here added.

Very probably some of those that made these reflections, were some distant relations of Joseph, or Mary; for as Jesus was now in his own country and city, and in his own native place, so among his kindred and relations; who envied his gifts and attainments, and objected to him his rise from that branch of their family, which was the most mean and abject.