How did God enter Yoga philosophy?

Much of the meditation teachings in the Pātañjalayogaśāstra (Yogasūtra and Vyāsabhāṣya) has been shown to be closely related to the śramaṇa traditions, especially Buddhism. The śramaṇa traditions were non-theistic. The Sāṃkhya system of thought, which is the metaphysical basis of the Pātañjalayogaśāstra is likewise a non-theistic tradition as is evident from its foundation text the Sāṃkhyakārikā. Īśvara was included in the Pātañjalayogaśāstra only in connection with descriptions of a meditation practice while the Yoga system remained non-theistic in its metaphysics. Īśvara is a special puruṣa, a puruṣaviśeṣa, in the sense that this puruṣa has never been bound to saṃsāra but īśvara here is clearly not a mainstream god. As a puruṣa, īśvara is contentless. In addition, when the structure of the divine world is described, in Pātañjalayogaśāstra 3.26, īśvara is not included in the divine world at all. Here Pātañjalayogaśāstra seems to be non-theistic. How is it then that the idea of a monotheistic-like God became so central in some later and contemporary interpretations of Yogasūtra and in traditions of yoga connected to that text? How to explain the entering of God in Yoga philosophy? The paper will argue for a non-theistic interpretation of Pātañjalayogaśāstra and suggest some reasons for the tendency to give monotheistic readings of īśvara in the Pātañjalayogaśāstra, which have implications for the contemporary understanding of Yoga.