The moed of Shavuot is also known as the Feast of Weeks (shavuot means "weeks"). In Christian nomenclature it is often called Pentecost (which comes from the Greek word pentekostes meaning "fiftieth"). It occurs about 50 days after Passover. In this moed we can see the Most High giving the Law at Mt. Sinai and then giving the Holy Spirit in Jerusalem 1,500 years later.
As we examine this moed and discover all that Scripture has to tell us about it, we should consider that it was the same very same G-d Who gave us the Law Who also gave us His Spirit. What does Scripture says about this festival and its related commandments? What are we to do and when are we to do it?