My husband has legal entanglement with another Jewish man. He has hired legions of attorneys to collect money on a judgment we could not possibly pay. Our net worth is less than two and a half million, his six hundred million and the judgment is five and a half million. His legions send messengers habitually on the Sabbath. We have asked politely to please refrain from this practice. Still the legions persist. Can another Jewish person disrupt a Jewish Family’s Sabbath?
It is forbidden for him to send demand for payment, in any form or via any messenger, on Shabbos. The Shabbos is precisely for rest from such matters, and as a Jew, he should be wary of profaning the Shabbos in this manner.
Of course, this does not have bearing on the actual content of the dispute.
Sources: This practice is included in the prohibition of daber davar, meaning that one’s speech on Shabbos should be distinct from one’s weekday speech.