But because they are weak in the other three bala, they are unable to practise kayagata-sati, or do the work of samatha and vipassana. Some persons are strong in the first three bala and thus can rise up to the work of kayagata-sati. They achieve concentration in out-breath, or in the bones of the body. But since they are deficient in the other two bala, they cannot rise up to the work of the jhana and vipassana. Some persons can rise up to the attainment of jhana samapatti because they are strong in the first four bala, but since they are weak in panna-bala, they cannot rise up to the work of vipassana.
Some persons are strong in panna-bala.
They are learned in the Dhamma and the Pitakas. But because the back is broken in the four other bala, they cannot emerge from the realm of tanha, kosajja, mutthasacca and vikkhepa. They live and die within the confines of these akusala. In this way, whenever one is deficient in any one of the bala, one cannot emerge out of the realm of the respective patipakkha. Hence, if these two bala are strong and co-ordinated, it does not happen that one cannot rise up to the work of vipassana because of the weakness of the other three bala.