Contradiction with Matthew 10:5-6
This verse instructs not to go to the Gentiles, whereas Acts 13:49 describes the word spreading throughout a region including Gentile lands.
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 Matthew 15:24
Jesus states he was sent only to the lost sheep of Israel, while Acts 13:49 shows the message spreading beyond Israel.
Matthew 15:24: But he answered and said, I am not sent but unto the lost sheep of the house of Israel.
Contradiction with Acts 16:6-7
These verses mention being forbidden by the Holy Spirit to preach in certain areas, contrasting with Acts 13:49 where the word spreads freely.
Acts 16:6-7: Now when they had gone throughout Phrygia and the region of Galatia, and were forbidden of the Holy Ghost to preach the word in Asia,
Contradiction with Genesis 11:8-9
God scatters people to prevent a single unified purpose, opposite to the unifying spread of God's word in Acts 13:49.
Genesis 11:8-9: So the LORD scattered them abroad from thence upon the face of all the earth: and they left off to build the city.
Contradiction with John 4:22
Salvation is said to be from the Jews, yet Acts 13:49 demonstrates the message of salvation spreading beyond Jewish borders.
John 4:22: Ye worship ye know not what: we know what we worship: for salvation is of the Jews.