Rinse lentils, put in a pot, and add water to cover by an inch.
Bring to a boil, then reduce heat to low and simmer for about 15 minutes, until lentils are just tender. Be careful not to over cook, or your lentils will be mushy.
Drain lentils and allow to cool.
Toss with all remaining ingredients and refrigerate for at least an hour to allow flavours to meld.
Notes
Both the capers and the olives are salty, so be sure to taste before adding salt.Make this recipe vegan by omitting the feta cheese or replacing it with a vegan feta.