Injunction/ restraining a person from causing nuisance in private gathering

Dear All, My query is as follows: Assuming Mr. A is getting married and it is contemplated that MR. X is planning to create nuisance in the marriage function in front of a gathering of 1000-1500 people. Mr. X has been threatening Mr. A and he happens to be a relative and nothing to do with the marriage (i.e., not a case where Mr. X is a GF of Mr. A etc) What are the PREVENTIVE remedies available to Mr. A.?

Would be grateful if you could provide detailed answers.

Thanks in advance :)