The subject and methods of meditation as taught in the suttas of the Pitaka are designed both for attainment of samadht as well as for development of Insight knowledge, Vipassana Nana, as a direct path to Nibbana
As a second step in the practice of meditation, after achieving samadht, when the concentrated mind has become purified, firm and imperturbable, the meditator directs and inclines his mind to Insight Knowledge, Vipassana Nana With this Insight Knowledge he discerns the three characteristics of the phenomenal world, namely, Impermanence (Aniccd), Suffering (Dukkha) and Non-Self (Anatta).
As he advances in his practice and his mind becomes more and more purified, firm and imperturbable, he directs and inclines his mind to the ^knowledge of the extinction of moral intoxicants, Asavakkhaya Nana He then truly understands dukkha, the cause of dukkha, the cessation of dukkha and the path leading to the cessation of dukkha He also comes to understand fully the moral intoxicants (asavas) as they really are, the cause of asavas, the cessation of asavas and the path leading to the cessation of the asavas
With this knowledge of extinction of asavas he becomes liberated The knowledge of liberation arises in him. He knows that rebirth is no more, that he has lived the holy life, he has done what he has to do for the realization of Magga, there is nothing more for him to do for such realization
The Buddha taught with one only object the extinction of Suffering and release from conditioned existence. That object is to be obtained by the practice of meditation (for Calm and Insight) as laid down in numerous suttas of the Suttanta Pitaka