From Shri Adi Shankara bhasya,
All the activities of the world in the form, ‘I eat this; I see; I
hear this; I experience this happiness, suffer this sorrow; I shall do
this for that purpose, I shall do this for this purpose; I shall know
this,’ etc. indeed arise owing to their being the objects of the
conscious witness. They verily exist in consciousness, and end in
consciousness. And such mantras as, ‘He who is the witness of this is
in the supreme heaven’ (Ṛg., Nā. Sū. 10.129.7; Tai. Bṛ.2.8.9), reveal
this fact. it follows from this that there is no other conscious
being apart from the one Brahman—who is the witness of all as the
absolute Consciousness, and who in reality has no contact with any
kind of enjoyment—, therefore there is no other enjoyer.
Hence, in this context, the question, ‘For what purpose is this
creation?’, and its answer are baseless—in accordance with the Vedic
text, ‘Who know (It) truly, who can fully speak about this here? From
where has this come? From where is this variegated creation?’ (Ṛg.
3.54.5; 10.129.6). And it has been pointed out by the Lord also: ‘Knowledge remains covered by ignorance. Thereby the creatures become
Everything is Nirguna Brahman, which is pure consciousness, existence and bliss. Creation is everything emerging from Brahman and going back to Brahman. Like waves from an ocean. There is only water though waves appears to be different. The waves appear to emerge briefly as a separate entity; however, just as quickly merge back into the ocean of which it is a part. Us, as human beings, are very much like the waves of the ocean. However, in reality, both wave and ocean are one, because both are really water.
The second Brahma-sutra states
We meditate on that supreme Truth—Brahman— in which all creation,
sustenance, and dissolution of the world take place.
As pointed out by Setu sir in the comments, in the commentary to the bhagavatha 1.1.1
Svarat is used to indicate that the cause is self-effulgent, and
independent of other causes. anvayat is used to indicate that Brahman,
as Existence, pervades the entire universe and yet the universe is not
As mentioned in the Isa Upanisad, Such a thing is pervading the whole Cosmos: īśāvāsyam idaṁ sarvam yat kiṁ ca jagatyāṁ jagat.
Thus, the above verse can be interpreted as advaita based on the commentary of Adi Shankaracharya.