Socrates was a very simple man who did not have many material possessions and spoke in a plain, conversational manner. Socrates often engaged in conversations with people who claimed to be "experts." He would question them on issues that, if they were the "experts" they claimed to be they would have the correct answer in seconds. Socrates often made these "experts" look quite foolish when he would prove them wrong in front of many other citizens. Plato's Euthyphro is about one day when Socrates was on his way to the courthouse he ran into Euthyphro (a young Athenian priest). Socrates began a discussion with Euthyphro about the definition of holiness. When asked about the definition of holiness, Euthyphro give Socrates three definitions and Socrates was able to prove all three of them to be wrong.
The first was that holiness was the life that Euthyphro lived. Socrates disputed this definition stating that even though the life that Euthyphro lived was holy, it was not the definition of holiness (if it was the exact definition then only Euthyphro would be holy). Next Euthyphro says that holiness is found in what is dear to the gods. Socrates shoots this definition down because this definition is not distinct, the Greek gods were somewhat human like, what was holy to one god might be despised by the next. The third and finally definition Euthyphro offers Socrates is, "what is holy is loved by the gods." However Euthyphro can't answer weather something is holy because it is loved, or loved because it is holy, making this final definition unjust.
All of Euthyphro's definitions are examples of holiness. During Plato's Apology, Socrates reveals his definition of holiness to a courtroom full of jurors. Socrates explains that holiness is serving the gods by serving other using ones abilities no matter what the consequence: and to know what is right is to do what is right. Socrates definition is just and universal. It does not single anyone out to be more holy then anyone else and allows anyone to be holy.