Srimad Bhagavatam #13: The Lord in the heart

At the end of each day of Brahma, the universe is partially destroyed and has to be recreated at the beginning of the next day. From the scriptures, we learn that although Brahma is very powerful, he is a living being, just like us. The soul inside the body of Brahma is not different from the soul in the body of an ant. How come Brahma can be so powerful to the extent of creating an entire universe, while the ant can just lift a grain of sugar?