CLAIM: Paul calls the Jews “dogs.” Does this the support the fact that Christianity was really birthed out of anti-Semitism?
RESPONSE: Paul was not anti-Semitic. In fact, he himself was Jewish, most of the early Christians were Jewish, and Jesus was Jewish! Instead, Paul was turning the tables on specific Jewish leaders, who were legalistic. It would be the same as someone arguing against a hypocritical politician. When we do this, we are not attacking all politicians; instead, we are attacking those who abuse their power or act unjustly. These Judaizers (i.e. these specific, hypocritical false-teachers) were trying to get Gentiles to circumcise themselves, following the Law of Moses. However, Christ fulfilled the Law of Moses (Mt. 5:17), so this was unnecessary. Moreover, the early church concluded that Gentile circumcision was unnecessary (Acts 15).
Paul calls these Judaizers “dogs,” because the Judaizers were notorious for calling the Gentiles “dogs.” In other words, Paul was turning the tables on these bigots, giving them a taste of their own medicine (see also comments on 1 Thessalonians 2:14-16). Finally, even Jesus used the term (“dogs”) to refer to hostile religious leaders who rejected his message of love and forgiveness (Mt. 7:6).
 Gundry, Robert Horton. A Survey of the New Testament. 4th ed. Grand Rapids, MI: Zondervan Pub. House, 2003. 432.