H/T Call me Jorge:
Messias-Deniers dancing on the White House lawn, and praying the Birkat HaMinim?
The Amidah prayer in its section twelve (formerly section nineteen) contains the Birkat HaMinim, the curse on Christians ("Ha' or 'la' 'minim"): Kerega karishah v'khol tikvah tehi al ve laminim ("Let there be no hope for the wicked and for Christians"). The curse has since been disguised by telling inquiring gentiles that the text is targeted not at laminim but at lamalshinim ("slanderers") and is aimed at malicious gossips, not Christians. The goyim usually believe this nonsensical cover story. It would be "antisemitic" not to believe it.
The truth, however, may be discovered in any uncensored edition of BT Berakhot 28b-29a. The failure to recite this section of the Amidah "prayer" was considered a sure indication that the Judaic who failed to say it was a crypto-Christian. Hence, recitation of the Birkat HaMinim was a litmus test to determine if a Judaic was secretly harboring Christian beliefs. In the past, Judaics who failed this test were subject to the rabbinic penal laws of the cherem, including beating, whipping and in extreme cases, execution.
The Birkat HaMinim prayer also consists in the supplication that Christians be "swiftly cut down (m'heriah... yika reitu)... doomed (toveid)... destroyed (ut mahgeir)" and "uprooted (fe'akeir)." Judeo-Churchians refer to this curse as a "blessing" — "the blessing of the Amidah."
source: Michael A. Hoffman II, Judaism Discovered (2008), footnote #272, p. 279