Siddhaḥ svatantrabhāvaḥ सिद्धः स्वतन्त्रभावः॥ (sūtra III.13)

siddhaḥ - attainment; svatantra – independence; bhāvaḥ - the state of being. 

This sūtra says that such an aspirant, who has crossed previous aphorisms, attains complete independence. Complete independence refers to the freedom from limited consciousness. When the aspirant is able to dissolve his limited consciousness into universal consciousness, he attains independence of his state of being. In this context his state of being refers to his inner self and not his physical self, as the aspirant has already ceased to attach importance to his gross self or gross body. The aspirant has already attained spiritual intuition as discussed in the previous sūtra-s. 

When the aspirant has achieved such an independence, he automatically realizes his inherent svātantryaśakti that is capable of controlling every aspect of the universe.  All along, he was afflicted with delusionary perceptions, as a result of which his svātantryaśakti remained hidden.  Now, after having got free of his limited consciousness by thoroughly cleaning his mind, he is able to realize his inherent and potential svātantryaśakti.

It is important to note that according to Triká philosophy that a spiritual aspirant must behold God while performing his duties. The aspirant continues to contemplate God all the time.