A term that usually refers to first-century Jews who claimed to be Christians but who still advocated adherence to the Mosaic Law and Jewish customs and traditions. They laid special stress on circumcision.

With their teachings, the Judaizers limited Christian freedom and caused divisions in the first-century Christian congregation. The apostle Paul counteracted their teachings, especially in his letter to the Galatians, where he refers to certain Judaizers as “false brothers.” (Ga 1:7; 2:4, 5; 4:9, 10; 6:12, 13; see also Ac 15:1, 2.) The “superfine apostles” mentioned at 2 Corinthians 11:5, 13 may also have advocated such views. The influence of Judaizers seems to have persisted for a number of years; Paul continued to deal with their ideas in his later letters.​—Col 2:11, 16, 17; Tit 1:10, 11.

While the word “Judaizers” does not appear in the Christian Greek Scriptures, the term is found in the writings of first-century Jewish historian Flavius Josephus. (The Jewish War, II, 463 [xviii, 2]) Paul used a related Greek term in his letter to the Galatians. At Galatians 2:11-14, he described how he corrected Peter at Antioch of Syria for refusing to eat with Christians from a non-Jewish background. Verse 14 uses the Greek verb I·ou·da·iʹzo together with the Greek verb for “compel” in the expression “compel . . . to live according to Jewish practice.”