Among the followers of every religion, doctrine or thought, one finds moderates and extremists. One even finds different subsects within every large sect. So, before holding a conviction about or attempting to have a relation with the followers of any religion or doctrine of thought, one should approach those who represent the mainstream and hold fast to the basic principles of their belief. It is of no use to approach an issue from the wrong end.
Responding to this issue, Dr. Muzammil H. Siddiqi said:
Dialogue is always helpful as it opens the doors for understanding and cooperation. However, when we choose representatives of any faith, we should try to choose those who represent the mainstream rather than those who say what we like to hear.
Many Jewish and Christian groups invite to their gatherings some Muslims who are critical of Islam and abuse Muslims. Thus, we criticize these groups and tell them that they should invite mainstream Muslims. Consequently We should do the same thing. We cannot have a real dialogue with any religion unless we try to converse with those who represent their main groups. From there, a real understanding and common ground can develop.
There is nothing wrong with meeting with the Rabbis of Neturei Karta, but one should bear in mind that they represent a very small Jewish group. But, again, one should not close the door on others.