Strength

Virtue: A particular moral Excellence; a Quality or Power;
Strength or  Courage; as the virtue of temperance, of chastity, of charity

Virtue comes from the latin word 'Virtus' meaning 'strength.'
This word originated in the Roman Empire and originally represented a brave warrior and over time came to represent a good man, or someone who did the right thing.

If someone is virtuous they live by a high set of moral values now.
Because they live by those values, they will strive for them and realign themselves often.
Because of this, they are exceptionally strong (virtus).

They live with a strict set of limits and clearly defined "I will" and "I will not" and they have the courage to live by them.
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