In the universe there are infinite sentient beings, including all enlightened beings. All these beings, either enlightened or in samsara, have the same base. One of the most important things we learn in Dzogchen is what the base is. The base is our real condition. When we explain the base, we use the explanation of essence, nature and energy. There is no difference, enlightened or not. That is why in Dzogchen we say that since the beginning our state is the enlightened state. Our real base or condition never changes or is modified. If we follow the teaching and use methods or practices for purification, we purify obstacles, but that doesn't change our nature. Our real condition is the same base since the beginning.
--Chogyal Namkhai Norbu