Many Jews today know little or nothing about whether there was a real historical Exodus, let alone whether there were ten miraculous plagues—all by the hand of God. It is too distant, and so much has happened since. The Sabbath is now more symbolic than a vivid, genuine commemoration of freedom from Egypt and its gods.
There is—Jesus knew this—a clearer event: the resurrection of Jesus. Admittedly, this too is so distant that its historicity is questioned by many, but to many believers, it is more real than the Exodus. Both events were proofs of the Father’s power over all other entities. The might of Rome and its gods could not prevent the resurrection, nor could the powers of the Sanhedrin. Victory—even over death—is proven by Jesus’ resurrection.
God should be honored frequently for both of these great victories, even today, as they demonstrate what it means that He is God. Ultimately, the resurrection at Jesus Christ’s return will again prove that God is God. Perhaps a new Sabbath will soon commemorate this. It is all about God being regularly and frequently honored as the liberator of His people who hope in Him.
If you are not a Jew, the memory of the Exodus is not significant enough to be celebrated weekly, though you might join in if those around you are Jews who genuinely celebrate it. The resurrection, however, is more relevant to both Jewish and non-Jewish believers in Christ. This is why Sunday is overtaking Saturday—it is simply reality.
Jesus knew he was the light of the whole world for all time, not just for Jews in ancient Roman times. He understood that honoring his Father as the liberator of those who hope in Him—the one true God—would require flexibility in how it was managed over the centuries, across Jewish and non-Jewish disciples and the surrounding people. As Lord over it, he appears to have left it open and flexible to be dynamically managed.