Just as the Gita modified traditional Sankhya with respect to the status of the Purusha, the Gita now has to take up the unresolved issues of the relation between Purusha and Prakriti with respect to this modification. Having presented the concept of 3 statuses of the Purusha (active connected to Prakriti, inactive unconnected to Prakriti, supreme Purusha encompassing both the active and the inactive), we need to now understand how the Gita proposes to address the question of Prakriti or Nature.
In traditional Sankhya, Nature is divided into 24 principles, of which one, the ego-sense, represents the individualising principle within Nature. The Gita’s active Purusha does not fit within this schema anywhere. Sri Aurobindo describes the issue: The 24 principles …”is a perfectly valid account for the apparent operations of the cosmic Prakriti with its three Gunas, and the relation attributed to Purusha and Prakriti there is also quite valid and of great use for the practical purposes of the involution and the withdrawal. But this is only the lower Prakriti of the three modes, the inconscient, the apparent; there is a higher, a supreme, a conscient and divine Nature, and it is that which has become the individual soul, the Jiva. In the lower nature each being appears as the ego, in the higher he is the individual Purusha. In other words, multiplicity is part of the spiritual nature of the One. This individual soul is myself, in the creation it is a partial manifestation of me…and it possesses all my powers; it is witness, giver of the sanction, upholder, knower, lord. It descends into the lower nature and thinks itself bound by action, so to enjoy the lower being: it can draw back and know itself as the passive Purusha free from all action. It can rise above the three Gunas and, liberated from the bondage of action, yet possess action, even as I do myself, and by adoration of the Purushottama and union with him it can enjoy wholly its divine Nature.”
It is important to understand these distinctions so that as we follow the thread of the Gita’s teaching, we can understand the framework upon which it is based, and how it differs from some of the more traditional views that held sway at the time this teaching was presented to Arjuna as the basis for his rising to a new level of understanding.
Sri Aurobindo, Essays on the Gita, First Series, Chapter 8, Sankhya and Yoga, pp. 73-74,