The persistent tendency of some—including Christians—to appeal to the Old Testament to justify, defend, or draw comparisons between Christian and Islamic teachings and practices reveals a fundamental misunderstanding. The Law of Moses under the First Covenant is not the same as the Law of Messiah under the New Covenant. This confusion underscores precisely why I wrote Jesus Practiced What He Preached.

For Christians, the relevant comparison is not between Muhammad and Moses, but between Muhammad and Jesus. We all know that under the Mosaic Law, and even before it, warfare, polygamy, slavery, and other practices were permitted or regulated. But Christians are no longer under that system summarized by the Law of Moses but under the Law of Messiah (1 Cor. 9:20–21; Gal. 6:2).

Jesus was sent to establish the new covenant summarized by his preaching of the gospel of the kingdom of God (Luke 4:43; 16:16; cf. Heb. 2:1–4). Unlike the laws of the Old Covenant, Jesus now commands his followers to love their enemies (Matt. 5:44), reject retaliation (Matt. 5:39; 26:52), and proclaim the gospel—not through violence, but through self-sacrifice, even unto death if necessary (John 18:36). The church is therefore no longer under what Paul calls a “tutor” or “guardianship” of the Law, but under the Messiah’s own new-covenant law.

The decisive question, therefore, is not what God permitted in the OT as a whole, but what God now commands through His unique human Son and Messiah. To appeal to the Torah to justify practices contrary to the teachings of Jesus and his apostles is to confuse two different covenantal systems and to undermine the greater authority of the Messiah over even the Old Testament patriarchs, prophets, and Moses himself.

Christianity must be measured by the preaching and practice of Jesus and the early churches, not by selectively invoking provisions of a covenant law that Scripture itself declares “obsolete” (Heb. 8:13) and under which his followers are no longer called to live.