World is a part of my self In Yoga of divine glories :WS 77: Bhagvad Gita in Managing self
In all these chapters Krishna, was giving details, about how he has expressed in the world . But in the concluding verses, he tells to Arjuna that the whole world is infact a part of him which means it is an express<
ion of him . So here he summarizes all that he had spoken in the earlier verses.