Contradiction with Matthew 15:24
Jesus says he is only sent to the lost sheep of the house of Israel, whereas Acts 26:17 indicates a mission to the Gentiles.
Matthew 15:24: But he answered and said, I am not sent but unto the lost sheep of the house of Israel.
Contradiction with Matthew 10:5-6
Jesus instructs the disciples not to go to the Gentiles, in contrast to the mission to Gentiles implied in Acts 26:17.
Matthew 10:5-6: These twelve Jesus sent forth, and commanded them, saying, Go not into the way of the Gentiles, and into [any] city of the Samaritans enter ye not:
Contradiction with Genesis 12:1-3
God’s promises to Abram focus on Israel, while Acts 26:17 extends the mission to Gentiles as well.
Genesis 12:1-3: Now the LORD had said unto Abram, Get thee out of thy country, and from thy kindred, and from thy father's house, unto a land that I will shew thee:
Contradiction with John 4:22
Salvation is said to be of the Jews, potentially opposing the inclusive mission to Gentiles in Acts 26:17.
John 4:22: Ye worship ye know not what: we know what we worship: for salvation is of the Jews.
Contradiction with Isaiah 2:3
Suggests nations will come to Israel, whereas Acts 26:17 highlights a mission from Israel to others.
Isaiah 2:3: And many people shall go and say, Come ye, and let us go up to the mountain of the LORD, to the house of the God of Jacob; and he will teach us of his ways, and we will walk in his paths: for out of Zion shall go forth the law, and the word of the LORD from Jerusalem.