The four noble truths
When we talk about Dhamma, although we may say a lot, it can usually be brought down to four things. They are simply to know suffering, to know the cause of suffering, to know the end of suffering and to know the path of practice leading to the end of suffering.
This is all there is. All that we have experienced on the path of practice so far comes down to these four things. When we know these things, our problems are over.
Where are these four things born? They are born just within the body and the mind, nowhere else. So why is the teaching of the Buddha so detailed and extensive? This is so in order to explain these things in a more refined way, to help us to see them.
When Siddhattha Gotama was born into the world, before he saw the Dhamma, he was an ordinary person just like us. When he knew what he had to know, that is the truth of suffering, the cause, the end and the way leading to the end of suffering, he realized the Dhamma and became a perfectly Enlightened Buddha.
– Ajahn Chah
Ajahn Chah biography:
With thanks to Just Dharma Quotes