Link:- In the previous verse, Lord Krsna explained that he who knows in reality His divine glory and power, is endowed with unfaltering Yoga of devotion. What is meant by unfaltering Yoga of devotion? The answer comes in the next verse.
aham sarvasya prabhavo mattah sarvam pravartate
iti matva bhajante mam budha bhavasamanvitah
I am the cause of the whole creation; from Me all things move. The wise knowing this and full of faith and devotion, continually worship Me viz., they take refuge in Me alone. 8
[Whatever, was said in the previous verse, that what is seen, heard and known is nothing besides the divine glory, of the Lord, is repeated in this verse. The power through which their manifestations appear is His divine yoga. It is expressed through the word Mattah. Whatever, has been said in the seventh, eighth and ninth chapters, has been condensed in the first line of this verse.]
Aham sarvasya prabhavah:- The Lord is the material and efficient cause of all creatures, born through mind, word, semen, earth, womb, egg, sweat viz., He is the origin of the whole creation, sentient or insentient, moving or unmoving.
He is the material cause, as well as the efficient cause, of the entire creation. It means, that He has manifested Himself, in the form of the entire creation.
Mattah sarvam pravartate:- Everything, in the world moves, because of the Lord. As electricity manifests itself, in various forms in instruments suited to those forms, the Lord, is the root of all the worldly actions.
Aham sarvasya pravartate:-The Lord says that a striver, instead of paying attention to various feelings, actions, things and persons etc., should behold the Lord, Who is the origin of all of them.
The Lord, uses the term 'Mattah' (from Me), again and again, as in the seventh and the twelfth verse of the seventh chapter and fifth and the eighth verse of the tenth chapter, to emphasize the fact that all feelings, actions and creatures etc., emanate from Him, remain established in Him, and merge into Him. So if a striver, either knows or assumes this fact, that in the entire universe, there is nothing else, besides the Lord, he will have unwavering unity (Yoga), with Him.