Role of God in Yoga : The question of determining the relation of Ishvara to the souls was one of the main problems of the Yoga philosophy.In Yoga the subject of Ishvara is of secondary interest,whereas to the main interest is to remove the afflictions of the citta by the cultivation of dispassion and habits of concentration for the release of the purusha;Ishvara is described only as being one of the many objects of concentration:by fixing the attention on Him the yoga goal may be achieved in a more convenient manner,as He may be pleased to remove the obstacles of the yogi and thereby make the way smoother for the yogin;there is also a general belief in Him that He is the Father of us all and the dedication of the fruits of all actions to Him has been described as being one of the principal ways of purifying the mind.Flint,rightly says that in order to think of God as a cause,to apprehend the universe as an effect,we must have some direct experience of causation.And such experience we have only in the consciousness of volition.When the soul wills,it knows itself as an agent,as a cause.The yoga attributed all movements and changes to the prakriti the primal matter.It was difficult therefore to assign any place to Ishvara consistently with its system of metaphysics.It is ,therefore,that we find that in the Yoga Sutras Ishvara is but loosely introduced,more as a matter of traditional faith than as having a place in the system of philosophy.He is introduced as only one of the alternative objects of concentration.He is Himself but a Purusha,with this difference that unlike them He had never the least semblance of any connection with the prakriti.He had never any ignorance,karma,the fruits of karma or the residual instincts of karma as vasana.He has in Him the seed of highest omniscience.As He is not limited by time.He is the preceptor of all past teachers even.Yoga as a system of mental discipline had originally existed independently of Samkhya and it was subsequently incorporated into the Samkhya school.It is probable,therefore,that the belief in an Ishvara was associated from the earliest times with yoga traditions as being revealed by the spiritual experiences of the yogi.

Prof. Gorbe’s remark that Patanjali,the founder of the yoga  of apersonal god in the hope that he would thus make the Samkhya philosophy acceptable to the countrymen is more an example of ingenious imagination than a fact justified by tradition andevidence.Had Patajali introduced Ishvara from such prudential considerations he would have been a little more cautious and have given his Ishvara a place in the system of his philosophy,instead of keeping him in a floating condition.

Yoga differs from Samkhya in this that it holds the existence of Ishvara necessary for salvation,whereas the Samkhya holds that salvation comes by knowledge .Vyasa says that Ishvara has a pure body made of the purest sattva,and the evidence that we have of its existence is the creation of the shastras and if the body had not been so pure the shastras could not have been so pure and infallible.It is on account of pure body of Ishvara that he can have knowledge and action by which he  could produce the sashtras and it is from the sashtras again that his pure nature could be inferred;such is there mutual relation from eternity.He who has no equal and who has the ultimate perfection of powers and omniscience is Ishvara.He has nothing to realize for himself but he acts for the good of all beings and gives instruction in true knoeledge and virtue for the emancipation of men.The pranava or the omkara has from eternity been the name to designate him.

Vacaspati,however,tries to find out a place for Ishvara by conceiving him elsewhere as removing the barriers of the prakriti.Ishvara removes the barriers of the prakriti in accordance with the merits and demerits of men and as a result of that she can flow of herself to fulfil the purposes of the purushas; for merits and demerits being but modifications of the prakriti cannot of themselves remove her barriers and all purushas are absolutely inactive.Vacaspati holds that at the time of the pralaya,Ishvara renounces his body with a desire that it should rise up again when the period of creation commences.Vijnanabhikshu differs from Vachaspati in holding that the pure body of Ishvara never returns to prakriti during the pralaya but that he is always in possession of his pure body,for Ishvara,pure body cannot be regarded as being either limited by time or as possessing potency or samskara which is due to avidya.Bhikshu says in the Vijnanamritabhasya that the yoga in order to avoid the difficulties of meeting the imputations of a partial or a cruel Ishvara has accepted the independence of prakriti in all its winding and unwinding process.With that pure body Ishvara has His joyous experiences though he has no bondage of abhimana with them,as is the case with ordinary purushas.It is because Ishvara does not identify Himself with His happiness that He is generally spoken of as nirguna or without any attribute.It is by His will that the purushas are connected wiyh the prakriti.The disturbance of the prakriti is also due to Ishvara’s will.The purushas are regarded asmere sparks of Ishvara.Purushas are the parts of which Ishvara is the whole.The reality therefore of prakriti and purusha cannot be distinguished from the reality of the Ishvara,through their separate existence as such is not denied.Bhikshu,however,controverts the Vedanta view of one Brahma-intelligence as appearing as Ishvara and the individual souls.Ishvara here in the theological aspect appears as the father of all.So long as we are under the bonds of passions and afflictions we are separate from Him though in reality we are still in Him:but as soon as these are removed we are free in our essence and again one with Him;though wedo not still lose our identity as ourselves all the while.Thus the prakriti in the yoga system was generally regarded as being presided over by Ishvara though there was a difference of views as to the exact nature of His influence.