In today's gospel we have two different conversations in three sentences. The people tell Jesus that his mothers and relatives of this world are looking for him. Earthly people see the world through earthly eyes.
Jesus looks around and gives a spiritual answer: "My mother and brothers are they who hear they who hear the word of God and keep it!"
Worldly people speak in worldly ways, kingdom people speak the language of the kingdom. Jesus had the utmost love and respect for his mother here on earth but he used this opportunity to widen out the whole concept of redemption to include the whole world.
What had started in Galilee was now becoming more and more inclusive, now to every person from anywhere who heard the word of God and kept it, salvation was offered.