aparigraha without possessions, without belongings, non-accept; of gifts
sthairye by becoming steady, stable
kathamia how, in what way, in what manner, whence
sambodhah knowledge, illusion
Knowledge of past and future lives unfold when one is free from greed for possessions.
When one is steady in living without surplus possessions and without greed, one realises the true meaning of one's life, and all life unfolds before one.
Perseverance in this austerity leads to knowledge of one's past and future lives, which appear like reflections in a mirror. When the sadhaka is free of worldly aspirations, he is a krtarthan (a happy and gratified person).
Aparigraha means not only non-possession and non-acceptance of gifts, but also freedom from rigidity of thought. Holding on to one's thoughts is also a form of possessiveness, and thoughts, as well as material possessions, which needs to be shunned. Otherwise they leave strong impressions on the consciousness and become seeds to manifest in future lives. These cycles of life continue until the sadhaka is totally clean and clear in thoughts, words and deeds.
Aparigraha is the subtlest aspect of yama, and arduous to master. Yet, recurring attempts must be made to benefit pure knowledge of 'what I am' and 'what I am meant for'.
This judicial thinking helps one to plan one's future lives from this present life. This is what Patanjali specifies when he says that the pattern of future lives unfolds to an aparigrahin.