In Jainism, mangalsutra has no scriptural or spiritual power. It is a cultural ornament, mainly from Hindu tradition, and is not a Jain religious requirement (even Jain weddings traditionally do not depend on mangalsutra).

So, if a mangalsutra breaks or gets cut:

1. No bad omen as per Jain dharma

- Jain Agams do not say that the husband’s life is in danger, or that something bad must happen. - It is just a physical object that broke – nothing more.

1. Friday or any particular day has no special fear-value

- In Jainism, days (Monday, Friday, etc.) are not “dangerous” by themselves. - What matters is your bhav (inner feelings), not the calendar day.

1. What should you do practically?

- Calmly get it repaired or replaced if you wish, just like any other jewellery. - If your mind became very scared or negative, you can do a small Namokar Mantra, or a short pratikraman to clean fearful/attached thoughts. - Try to reduce mithyā shraddhā (superstitious belief). Remember: - Karma is bound by intentions and actions, - Not by a thread or ornament breaking.

1. Jain view on such ornaments

- For shravaks/shravikas, simple ornaments are allowed but attachment and superstition are discouraged. - More focus should be on ahimsa, satya, aparigraha, samayik, pratikraman, etc., not on signs/omens.

So, as per Jainism: If mangalsutra breaks on Friday, nothing automatically bad happens. Stay peaceful, repair it if you want, and focus your faith on Jinendra Bhagwan and your own right conduct, not on fear.

For related information on adornments like mangalsutra from a Jain angle, you can read more here