John Calvin Commentary Matthew 14:1

"At that season Herod the tetrarch heard the report concerning Jesus," — Matthew 14:1 (ASV)

The reason the Evangelists relate this occurrence is to inform us that the name of Christ was known everywhere, and therefore the Jews could not be excused by pleading ignorance. Many might otherwise have been perplexed by this question: “How did it happen that, while Christ lived on the earth, Judea remained in a profound sleep, as if he had withdrawn into some corner and had displayed his divine power to no one?” The Evangelists accordingly state that the report about him was spread everywhere and penetrated even into the court of Herod.