At one stage Rabbi Levy urged congregants to focus on the service rather than on the content of the chat room.
Eventually a decision was taken to shut the chat room down as the service continued.
The JC has spoken to two Alyth members who said they had been left "shocked and upset" by the incident.
One said: "Because of the coronavirus pandemic it was a highly emotional and very important service to be able to watch online.
"The last thing I expected to see was extreme racist and antisemitic hate messages appearing on the chat room.
"It was most upsetting, and shocking to watch this going on from the computer in my living room."
Rabbi Levy told the JC the abusive messages were “an intrusive violation of our sacred space. The incident has been reported to the CST and police and we have taken steps to ensure it will not be possible for anyone to interrupt our services like this in the future.
"One of the founding ideals of our community is that we should welcome those who wish to join us for prayer. We will continue to do so as much as is possible during these challenging times.
"It is deeply upsetting that at such a difficult period we are faced with additional challenges like these. We will be keeping the security of our online provision under review through the weeks ahead.”
