Paul points to Christ to make it clear that they should not seek their own interest, but the interest of others (see Philippians 2:4–8). Instead of causing to stumble (Romans 14:13, Romans 14:20–21), tearing down (Romans 14:20) or damaging (Romans 14:15) our neighbour, we are to build him up. Edification is a constructive alternative to demolition. And this upbuilding of the weak will doubtless include helping to educate and so strengthen their conscience.
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1 Nous qui sommes forts, nous devons supporter les faiblesses de ceux qui ne le sont pas, et ne pas chercher ce qui nous plaît.