The Three Attainments - Attainment of jhana

An ordinary person who is not an ariyan may attain jhana and acquire the skills (vasís) in jhana, such as attaining jhana and emerging from it in the order of the successive stages of jhana. Someone who is proficient in jhana can have jhana-samapatti, that is, jhanacittas arising in succession in a mind-door process without bhavanga-cittas in between, for a period lasting as long as he has determined. During that time he is free from pain and unhappiness. This is because he is free from the sense objects and experiences only the meditation subject of jhana, which conditions the happiness of true calm.