Contradiction with Matthew 10:5-6
Jesus instructs the disciples to avoid Gentile and Samaritan towns, contradicting the acceptance of the Samaritans in Acts 8:14.
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 John 4:9
The Samaritan woman points out Jewish refusal to associate with Samaritans, contrasting with the acceptance seen in Acts 8:14.
John 4:9: Then saith the woman of Samaria unto him, How is it that thou, being a Jew, askest drink of me, which am a woman of Samaria? for the Jews have no dealings with the Samaritans.
Contradiction with 2 Kings 17:24
The introduction of foreign peoples to Samaria leading to mixed worship practices contrasts with the unified Christian message in Acts 8:14.
2 Kings 17:24: And the king of Assyria brought [men] from Babylon, and from Cuthah, and from Ava, and from Hamath, and from Sepharvaim, and placed [them] in the cities of Samaria instead of the children of Israel: and they possessed Samaria, and dwelt in the cities thereof.