Composed in the late 12th or early 13th century by a German Jew, Ma’oz Tsur (“Mighty rock”) is the best known Hanukkah hymn. Modern scholars have long thought that its sixth and final verse, a prayer for future redemption, was added by a later author. Yitzhak Melamed argues otherwise:
To the best of my knowledge, the sixth stanza first appeared in print in Amsterdam in 1702. The fact that the sixth stanza was first printed only hundreds of years after the hymn was written has led some scholars to suggest that it is not original but a later addition. Nevertheless, the intricate style of the sixth stanza is identical to that of the first five stanzas, and it complements almost perfectly the topic of the first stanza. Thus, the last stanza [appears to have been] intentionally repressed and passed by oral tradition for almost five centuries due to its strong anti-Christian theme.
The first line begins by beseeching God to “expose his holy arm,” an expression referring to God’s violent redemption of the Hebrews from Egypt “with a mighty hand and an outstretched arm” (Deut. 26:8). . . .
Against whom is God meant to apply his mighty arm? The phrase which follows may mean simply: “bring the end, the redemption.” But the text may have a [coded] meaning as well: “bring the end of Jesus-ism.” In other words: “Bring the end of Christianity.” The intentional double meaning of y’shua as salvation, on one hand, and as a collective noun referring to the followers of Jesus [in Hebrew, Y’shua], on the other, allowed the medieval Jews to assert and conceal their hatred of Christianity at the same time.
The succeeding line is a natural continuation of the hidden meaning of the opening line of the stanza: “Avenge the abuse of your servants / From the wicked nation.” The term “wicked nation” is a standard rabbinic reference to Rome and Christianity, and the historical context of the hymn, [an] era of massacres [of Jews] perpetrated by the Crusaders, explains the desire for revenge and the urgent request for redemption expressed in the third line.