From the FAQ: Is it virtuous to do thus-and-such?
Virtue is excellence of one's character or rationality, rather than body, anything that happens to one, or anything one achieves. When "virtuous" or "vicious" are used to describe what one does, the virtuousness or viciousness of the act depends on the virtue or vice of the character traits leading to the act. Where the central question of much modern ethics revolves around what specific acts are moral or immoral, this doesn't seem to have been how the classical Greeks even thought about the question. The focus of their attention was on character; if one develops a virtuous character, moral acts follow naturally.
How would a Stoic blow their nose? "Where the central question of much modern ethics revolves around what specific acts are moral or immoral, this doesn't seem to have been how the classical Greeks even thought about the question."
"…if one develops a virtuous character, moral acts follow naturally."
Stoicism is a virtue ethic.
Virtue ethics is currently one of three major approaches in normative ethics. It may, initially, be identified as the one that emphasizes the virtues, or moral character, in contrast to the approach that emphasizes duties or rules (deontology) or that emphasizes the consequences of actions (consequentialism). SEP
“Yes, but my nose is running.” What have you hands for, then, slave? Is it not that you may wipe your nose? “Is it reasonable, then, that there should be running noses in the world?”—And how much better it would be for you to wipe your nose than to find fault! Discourses 1:6
An example of "to find fault" with your nose running would be to make a false judgment, such as, "My nose should not run."
What is ‘virtue’ in Stoicism? Virtue is a form or expertise or skill, knowledge how to live well in every way, a form of knowledge that shapes the whole personality and life. Virtue is analysed in terms of four generic or cardinal virtues: wisdom, courage, self-control or moderation, and justice, seen as either four aspects of a single form of knowledge or as interdependent.
Link to this excellent article on virtue.
It is helpful for me to think of virtue as a skill. To gain a skill takes practice.