Matthew 15:24

But he answered, and said
To his disciples, who knew how limited their commission was, that they were not to go into the way of the Gentiles, not to preach to them, nor perform miracles among them; and therefore could not reasonably expect that either the woman, or they, on her behalf, should succeed in this matter.

I am not sent, but to the lost sheep of the house of Israel;
as a priest, or as a Saviour and Redeemer, he was sent to make satisfaction and atonement for the sins of all God's elect, and to obtain eternal redemption and salvation for all of them, whether Jews or Gentiles; but as a prophet, in the discharge of his own personal ministry, he was sent by his Father only to the Jews; he was the "minister of the circumcision", ( Romans 15:8 ) that is, a minister to the circumcised Jews; he was sent only to preach the Gospel to them, and work miracles among them, in proof of his Messiahship; and upon their rejection of him, then his apostles were to be sent among the Gentiles; but he himself was sent only to the Jews, here styled "the lost sheep of the house of Israel": by "the house of Israel", is meant the whole body of the Jewish nation, so called from Israel, the name of Jacob their father, from whom they sprung; and by the "lost sheep" of that house, are more especially designed the elect of God among them: for though all the individuals of that house were "lost" persons, considered in Adam, and in themselves, as the rest of mankind, and Christ, in the external ministry of the word, was sent to preach to them all; yet the elect of God are only "sheep": they are the sheep of Christ, of his pasture, and of his hand, whom he has the particular care and charge of; and who, in their natural state, are lost and straying, and could never find their way, or recover themselves from their lost state in Adam, and by their own transgressions; but he came to seek, and to save them, and to these his ministry was powerful and efficacious.