Earth is like a giant battery, it provides us with natural energy. 
In the world today with so much technology and noise our own energy can get mixed up with energy from other, technology, places, objects etc.....
By grounding we are re establishing our connction with the earths energy this has multiple health benefits including, helping with anxiety, depression, pain, inflammation and many many more health benefits. this also help your energy to be in the hear and now. 
Meditation length 3:45