(JNS) — In the aftermath of the Oct. 7 Hamas massacre and the subsequent onslaught of antisemitism, Christians have an opportunity to write a new chapter in their history; one in which they show up as allies and friends of the Jews. Thousands of Christians around the world are doing just that.

The long and painful history of Jewish-Christian relations has seen few heroes and many moral failures. Both Protestantism and Catholicism, at different moments in their history, adopted antisemitism as doctrine. One famous example was Pope Paul IV’s Cum Nimis Absurdum, in which he called for Jews to liv...