It is hard to imagine a more embarrassing situation in which to find an exclusive ultra-Orthodox organization - a group that was a standard-bearer in the fight against "breaches in the wall of conversion" and "the penetration of complete gentiles into the vineyard of Israel."

These breaches pale into insignificance in comparison with the accusations against the man who heads the organization itself: according to the claims, Rabbi Leib Tropper of Rockland County abandoned the apparently stringent Halakhic standards of his Haredi organization and established a conversion process based on his most private impulses.

A report in the New York Post earlier this week revealed a sensational story about "a prominent Orthodox rabbi has been caught on tape discussing his apparent love affair with a shiksa he was converting to Judaism."

The woman involved is 32-year-old Shannon Orand of Houston, who still seeks to convert from Christianity to Judaism. The bulk of the report deals with embarrassing comments that the rabbi made during a phone call, during which he was recorded demanding the woman perform a number of sexual services for himself and his friends in exchange for granting her a conversion certificate.

Only at the very end of the Post report is it mentioned that at the start of the month, Rabbi Tropper resigned from his position as head of the Eternal Jewish Family organization, which dealt with conversions. But the connection to the group is in fact the story's punch line, making the affair another incident in the ongoing crisis in the world of conversion.

This connection also explains the extent to which an alleged case of blackmail has rocked the rabbinic world in Israel and the United States, and also has a complex relationship with the business dealings of the chairman of the Beitar Jerusalem soccer club, Brazilian Jewish entrepreneur Guma Aguiar.

Rabbi Tropper's stated goal in founding the Eternal Jewish Family was to "fortify the walls of conversion," amid an ideological debate between the Haredi and national camps in Israel. While functioning as a well-known rabbi in the New York area and head of the Kol Yaakov yeshiva, Rabbi Tropper enlisted wealthy Jews in the Haredi fight against to non- ultra-Orthodox conversions, especially those carried out by special conversion courts in Israel headed by Rabbi Haim Druckman.

As such, the doors of senior Haredi officals were thrown open to him, including that of Rabbi Shalom Elyashiv, a leader of the Lithuanian Haredi sect, and rabbi Tropper himself had the title of gaon ("most learned") bestowed upon him by the ultra-Orthodox press - all because of his efforts and comments against conversions by the Conversion Authority, against the "infiltration" of gentiles into the people of Israel.

When news of the affair began to emerge two weeks ago, posters denouncing Tropper were plastered across the Haredi city of Bnei Brak, whose title commanded: "Leave impurity." The text's anonymous authors threatened that if he did not quit the organization, "We will publicize our voice aloud, accompanied by pornographic pictures and shocking video clips." The rabbi did indeed announce his resignation, but failed in his efforts to hush up the affair.

It was leaked to American Jewish bloggers, the audio tape was posted on YouTube, and the Post published the story (under the headline "Tal-mood for love: Sex-tape rabbi tries to 'share' hottie," referring to one of Tropper's demands in the tape).

The current scandal is not the first in which the Eternal Jewish Family and Tropper have been involved. Tropper recently accused Aguiar of assaulting him in a Jerusalem hotel in April while the rabbi served as a prosecution witness against the businessman in a civil suit in Florida. Aguiar - who recently resigned from the organization - is accused of entering Rabbi Leib Tropper's room at the David Citadel Hotel, assaulting him and threatening to cause him further harm.

At the time of the alleged attack, Tropper was testifying at Aguiar's trial on embezzlement charges brought before a Florida court by the businessman's uncle, Thomas Kaplan.

As part of a war of slander between the pair, a notice was published in the Haredi newspaper Hamevaser, according to which rabbis close to Aguiar gave up their stringent halakhic demands with regard to his wife. The notice alleges that the businessman is "married to a woman who underwent a very dubious conversion."

Tropper's associates claim that Orand, the tape and the posters are all connected to this legal dispute. One of the associates told Haaretz that, "Guma Aguiar succeeded in throwing Rabbi Tropper to the trash."

Saul Sadka contributed to this article