In the evening after Sujata's lovely meal, Gotama went to Gaya and looked for a suitable place to sit down and meditate. He found a banyan tree and sat on its east side, the side that was believed to be stable and free from trembles and quakes. After sitting cross-legged with his back towards the tree, he made this resolution: "Though my skin, my nerves and my bones shall waste away and my life blood go dry, I will not leave this seat until I have attained the highest wisdom, called supreme enlightenment, that leads to everlasting happiness."
He meditated on his breathing in and breathing out. It was the eve of the full moon. During the first part of the night many evil thoughts, described as being like the evil god Mara and his army, crept into his mind. Thoughts of desire, craving, fear and attachment arose, yet Gotama did not allow these thoughts to disturb his concentration. He sat more firm than ever. He began to feel calm and brave as he let these thoughts go and so, in the first part of the night, he found the power of seeing his own past lives.
In the second part of the night Gotama realised the impermanence of life and how living beings die only to be reborn again. In the third part of the night he realised the cause of all evil and suffering and how to be released from it. He understood how to end sorrow, unhappiness, suffering, old age and death.