The joy of “Simchas Bais HaShoeivah” sensitizes us to see and know joy all through our lives. Although the Bais HaMikdash no longer stands we can still celebrate the joy of Bais HaShoeivah in its fullness. The first night of Sukkos is the gateway into the joy of Bais HaShoeivah. 
In Torah we read of the blessing to Levi, to teach Torah, and that G‑d hovers over Binyamin always. The Ushpizin constantly taught Torah. Our efforts in teaching must likewise be continuous. 
The Rambam lists the eating of the Passover offering as a separate mitzvah. The bondage was physical torture and the celebration of the Exodus must be physical. The Ushpizin also dealt with physical matters and we must bring the joy into the street with song and dance.