Christian Zionists Heresy of the Day by Joel Berry. Observing Shabbat as a religious obligation is considered historically heretical, when it is practiced as binding on Christians. The issue is not the day itself, but the claim that Christians are still bound by the Mosaic Sabbath law. The Sabbath commandment in the Mosaic Law was part of the Old Covenant, which was fulfilled and transformed by Jesus Christ in the New Covenant. Jesus Himself claimed authority over the Sabbath: “The Son of Man is Lord even of the Sabbath.” — Matthew 12:8 The Church teaches that Christ did not abolish the moral law, but He fulfilled the ceremonial aspects of the Mosaic Law: Christians claiming we are still bound to Mosaic Law (Shabbat) are committing a heresy because this denies Because this denies: •the New Covenant •the authority of the Apostles •the Resurrection-centered worship of the Church Historically this error was associated with Judaizing sects such as: •Ebionites •Nazarenes