If a Muslim is in a business partnership where their partner proposes a new venture contrary to Islamic ethics, they should:

1. Politely decline participation, citing Islamic principles
2. Explain the reasons and concerns in a respectful manner
3. Seek guidance from Islamic scholars or mentors
4. Review partnership agreements and exit clauses
5. Consider dissolving the partnership if necessary
6. Prioritize protecting their religious integrity over financial gains
7. Explore alternative, Shariah-compliant business opportunities

Remember, Islam emphasizes:

– Avoiding haram (forbidden) activities
– Upholding ethical standards
– Being truthful and transparent
– Protecting one’s faith and values

By taking these steps, Muslims can maintain their religious integrity while also being a responsible business partner.