Tasya Saptadha Pranta-Bhumin Prajna (II 27)
= His(Purusa's) Saptadha = sevenfold Pranta-bhumih
= a definite stage Prajna = the cognitive consciousness.
In his case the highest stage of Enlightenment is reached by seven stages.
Many a time a question arises in the mind of Sadhakas(practitioners of Yoga)whether one arrives at the Ultimate (Kaivalya)suddenly or gradually .There is no conflict in the two schools of thought. It can be both sudden as well as gradual depending upon how we look at it.
A labour goes on hitting a piece of rock to break it and at twentieth stroke it breaks. This does not mean that only twentieth stroke, suddenly, broke the rock. Even first hit was responsible to weaken the stone. We go on heating the water. It warms up to 20 degrees, 30 degrees till it turns into vapour at 100 degree centigrade. It may look, all of a sudden water evaporated, if we don't take in account the continuous heat from degree onwards and see only the vapour. Till boiling point arrives, the process, invisible to our eyes, goes on silently.
Similarly as we go on doing Sadhanas (spiritual practices)changes take place within, even without our knowledge sometimes, and then there is a feeling of sudden expansion. This Sutra here says that a Yogi reaches the state of Enlightenment gradually through seven states of consciousness. These states are also named in Yoga Vasistha as Sapta Bhumikas.