The phrase "most virtuous" is correct and usable in written English.
You can use it to describe someone who displays high moral standards, such as: "My grandmother was one of the most virtuous people I know."
The most virtuous of women.
Some people feel most virtuous throwing things out.
Those are most virtuous, perhaps, that cannot be pursued without strength and nobility.
These contain cream, unlike most virtuous and dull yogurts made with low-fat milk.
In fact, it may be the most virtuous restaurant in Manhattan.
Its actively purchased percentage was 87.0%, hardly making it the most virtuous magazine in existence.
Among them is that private financial interests can subtly sway even the most virtuous leaders.
If contempt and hatred were virtues, Gill was the most virtuous of men.
Only the shrewdest, most virtuous man in the world can undermine the worst one.
IF patience is a virtue, then AquaBounty, a Massachusetts biotech company, might be the most virtuous entity on the planet.
