Who is St. James from Catechism of the Catholic Church and what is their importance?

This canonized apostle comes up in the beginning of the second half of the Catechism. St. James emerges as a strong critic of blasphemies involving the misuse of God's name. Doubtless venerated for other reasons, this is the reference point readers have at the first mention of his name in this concise summary of the Catholic religion.