One may not even listen to words of Loshon Hora , even if he does not plan to believe the words.
However , one may listen if there is a chance it may bring about some benefit such as to protect oneself or others from trouble.
But he may only listen if the speaker also has constructive intentions or the speaker began talking to others before he came.
Thus if someone begins saying negative about someone , we should ask first - is this relevant for me in the future. ?
If someone complains about others , make sure to get all the details so that you can clarify & rectify the situation properly.
When one is only allowed to be careful , but not to believe the Loshon Hora , one may not act in any way different than to treat that person as a fellow Jew.
For example , if there were poor people who were eligible to receive charity , but now there are rumors that they are a fraud , one must still give them charity until the matter is clarified.
Now may be a good time for a gem of Torah study.
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