The Four Noble Truths – Chattari-ariya-saccani
The Four Noble Truths were first taught by the Buddha in the Dhammacakkappavattana Sutta (Pali: Dhammacakkappavattana Sutta, meaning “The Discourse on Setting the Wheel of Dhamma in Motion”). This sutta is found in the Saṃyutta Nikāya (SN 56.11) of the Sutta Pitaka in the Pali Canon. This is considered the first sermon of the Buddha, given to the five ascetics at the Deer Park in Sarnath after his enlightenment.