Arutz Sheva reports Rabbi Yosef Shalom Elyashiv, the 99-year-old haredi leader, has ruled taking money from the International Fellowship of Christians and Jews, headed by Modern Orthodox Rabbi Yechiel Eckstein, violates the prohibition of idol worship.
Rabbi Elyashiv added cooperation with IFCJ will aid future missionary activity.
It is unclear how taking money from Christians halakhicly causes Jews to violate the prohibition against idol worship – especially because most rabbinic opinions hold the Evangelicals themselves do not violate that prohibition, and the Jews receiving the money get it through existing Jewish organizations, many of them Orthodox.
A blanket prohibition against taking donations from Christians should mean, for example, money given by Christians to feed, care for and house Holocaust survivors in the immediate aftermath of WW2 caused those survivors to violate the prohibition of idol worship.
Rabbi Elyashiv's concern about future missionary activity without any mention of past missionary activity seems to support the idea that IFCJ does not engage and has not engaged in missionary activity up until now.
In early September, a Chabad rabbinical court also ruled IFCJ money is forbidden due to potential missionary activity.
The driving force behind these rulings appears to be Yad L'achim, a hredi anti-missionary organization headed by Rabbi Sholom Ber Lifshitz, a Chabad-Lubavitch hasid.
Lifschitz's organization has made several allegations of IFCJ missionary activity ion the past.
All those allegations were proved false.
Most of the false allegations were based on confusing (or intentionally distorting) basic Christian terminology and the English language.
An example of this type of error would be ruling the US-based United Jewish Communities money forbidden because it is involved in 'missionary work.' What 'missionary work'? It runs "missions" to Israel. Of course, those missions are filled with Jews, many of them Orthodox, who go to Israel to see the organizations they fund. There is no Christian missionary activity related to those missions or UJC.
Rabbi Elyashiv also reportedly claimed taking money from IFCJ is an "unclean act."
Other rabbis who have ruled it is forbidden to take money from IFCJ include Rabbi Shmuel Auerbach, Rabbi Nissim Kerlitz, Rabbi Ovadia Yosef, and Rabbi Mordechai Eliyahu.