परं ब्रह्म परं धाम पवित्रं परमं भवान्।पुरुषं शाश्वतं दिव्यमादिदेवमजं विभुम्॥
paraṃ brahma paraṃ dhāma pavitraṃ paramaṃ bhavānpuruṣaṃ śāśvataṃ divyam ādi-devam ajaṃ vibhum
Word by word
The verse says
Arjuna said: You are the supreme Brahman, the highest home, the purest thing there is. You are the eternal divine person, the first of the gods, unborn, present everywhere.
In plain words
Arjuna answers, and what comes out is not a question.
For eleven chapters he has been asking things. Here he simply says what he now sees, in a run of names.
It is the first time in the book he speaks like this.
Where you've felt this · in creative work
You listen to your neighbour describe her work for an hour and ask questions the whole time. Then at some point you stop asking and just say: you are extremely good at this. The sentence is not a question and does not expect an answer. Something had accumulated and needed saying.
Going deeper
Praise is a different kind of speech from enquiry, and the shift in Arjuna is the event here.
Everything he has said so far has been interrogative — how do I, what is, which of these. This is the first time he says something that asks for nothing. The content is not new; most of these titles have appeared earlier. What has changed is that they are now coming out of him instead of going into him.
That is a recognisable stage in understanding anything. There is a point where you stop collecting and start describing, and the describing is how you find out what you have understood.
It also explains the structure of what follows. Arjuna is about to ask for the long list of glories, and he asks as somebody already convinced. He is not gathering evidence. He wants more of something he has begun to enjoy.