This is the second discourse given by the Buddha to his five original ascetic companions after setting the wheel of the Dharma in motion. The Buddha gives his teaching on Anatta (or not-self), and the five become enlightened.
Do you ever get sleepy while meditating? In this discourse, the Capala Sutta from the Angutarra Nikaya, the Buddha catches one of his main disciples, Ven. Maha Moggallana nodding off. He then offers him seven strategies for overcoming "sloth and torpor". Identifying with the drowsiness can actually be a doorway to the wisdom of anatta or the selfless nature of reality.
