Krishna: All beings are in me, but I am not in them. He is pointing to maybe the greatest mystery of creation here. No matter how big we are physically, we can't even pervade a single room. And by universe, he means not only this physical universe, but all living beings also.
Swami Sarvapriyananda teaches Chapter 9 (Verses 3 - 4) of the Bhagavad Gita. In this series of talks, Swami Sarvapriyananda unfolds the highest truths of Vedanta through the study of the Bhagavad Gita (The Song of God).