Translations for profitable in French

Here are paragraphs from public domain books translated:

The king signed the order for release, and Treville carried it away without delay. As he was about to leave the presence, the cardinal gave him a friendly smile, and said, "A perfect harmony reigns, sire, between the leaders and the soldiers of your Musketeers, which must be profitable for the service and honorable to all."	Le roi signa l’ordre d’élargissement, et Tréville l’emporta sans retard. Au moment où il allait sortir, le cardinal lui fit un sourire amical, et dit au roi : — Une bonne harmonie règne entre les chefs et les soldats dans vos mousquetaires, Sire ; voilà qui est bien profitable au service et bien honorable pour tous.
The Three Musketeers, by Alexandre Dumas	Les Trois Mousquetaires, de Alexandre Dumas