Q. I learnt recently that a sentence had been omitted from Alenu. Can you give me details?
A. The sentence is from Isaiah 30:7 and 45:2. Contrasting Israel and the heathen nations, it says:
שֶׁהֵם מִשְׁתַּחֲוִים לְהֶבֶל וָרִיק, וּמִתְפַּלְּלִים אֶל אֵל לֹא יוֹשִׁיעַ
“For they bow down to vanity and emptiness and pray to a god that cannot save”.
Rav, who composed Alenu in 3rd century Babylon, probably never met a Christian, and Isaiah (8th century BCE) was clearly not attacking a religion that came into being nearly a millennium later; but in the medieval period baptised Jews claimed this sentence was anti-Christian.
Jewish scholars repeatedly protested that the accusation was preposterous, but it still led to antisemitic attacks. In Prussia in 1803 an edict was issued that the sentence was to be eliminated and the whole of Alenu was to be said aloud without it. Commissioners visited the synagogues to supervise the implementation of the edict.
The sentence is however today maintained in the Sephardi rite as well as in some Ashkenazi congregations.