There are many perspectives on this issue. But the answer to this question is rather simple. One issue with philosophy is that it has clouded many important debates in voluminous words and obscure theories. The books written on the subject are so difficult and confusing that they are not doing the good they must do to the society. The disparity between the understanding of a lay man and philosophy has harmed, in my opinion, the world.
The answer is very simple. There is no point in this argument that a person has to be virtuous in order to perform a virtuous action. The first problem with this statement is that who and how this virtuous man will be defined. According to Aristotle a person is virtuous if he displays a moderate behavior that is a behavior that is between the two extremes (Bostock, 2000). He also believed that virtue is something that can only be learnt and one is not born a virtuous man.
Without commenting on the Doctrine of Mean of Aristotle, I would like to agree with Aristotle on this part that virtue is acquired and is not something that a person enjoys from birth. The idea that virtue is learnt provides answer to our question. Virtue if learnt can be achieved by any person, and not just a virtuous person. Anyone can learn to become virtuous can in turn can perform a virtuous act.
Even if a person has not acquired all the traits of a virtuous person, he can perform a virtuous action if he has learnt that particular virtuous behavior. We should understand this by an example. A person who has all the traits of a virtuous man in considered virtuous. Now if there is a person who has only some traits of a virtuous man, like he is honest and just, but not all traits of a virtuous man (he is not courageous) then he can perform virtuous (just and honest) acts. He may not be courageous but he can perform a virtuous act.
If virtue is acquired and not granted by birth, then a person who is not courageous today can become courageous tomorrow. So