William Burkitt on Matthew 15:24

Observe, when our Saviour doth answer, he gives not one word of comfort, but rather a repulse. Christ has often-times love in his heart to his people, when they can read none in his countenance, nor gather it from his discourse.

Observe, the answer itself, Christ says not, I am to sent unto the lost sheep of the house of Adam, but to the lost sheep of the house of Israel. The Jews are compared unto sheep, the Gentiles unto dogs. Christ insinuates, that though they were a lost sheep of Adam, yet not being one of the lost sheep of Israel, he could do nothing for her. It was a common saying among the Jews, "That the nations of the world were likened to dogs, whereas they were God's sons and daughters."