Let me first of all steer clear of a possible misconception that may occur after reading this article. I am not a scholar of Hindu scriptures. I have not even learnt Sanskrit. But I did read a lot of spiritual teachings. Passing references to certain Upanishadic verses fascinate me. At the same time I do get a little sad to see, even stalwarts like Swami Chinmayananda having misconceptions about certain Upanishadic verses. For example he quotes a verse from, well, I think Mundakopanishad मूंदक उपनिषद्. It goes like this - "न तत्र सूर्यो भाति न चन्द्र तारकं I नेमा विद्युतो भाति, कुतोयम अग्निः I तमेव भान्तमनुभाति सर्वं I तस्य भासा सर्वमिदं विभाति I - meaning, - there the sun does not emit light; neither moon nor the stars do. Even lightning has no light, where is fire? You are the only light and from that everything else reflects; and that is how the illusion that all these have light. Chinmaya says this mantra is the main chant of worship in the temples while casting the mangalaarati (मंगलारती) to the reigning idol, which clearly means that the verse is in praise of God. This comes as a reference while explaining what is Brahman (ब्रह्मा). So, it means that the whole of universe is visible through the only light that You, the God Almighty emits. Whereas, Chinmaya, while giving an explanation to the meaning of 'Upanishad' says - उप is near; नि is below or lower level and शाद is listening. So Upanishads means listening to the master sitting near on the ground below. That clearly refers 'You' तम (तम + एव = तमेव) in the श्लोक - verse - to the listener, शिष्य or चेला ie., student, pupil, not God. So, you are the only light, certainly refers to the listener, the learner, not God!
God is my personal creation, because my God is what I want Him to be, right? Well you may not agree, but then you sure, will agree with learned spiritual luminaries and Swami Vivekananda, I hope is one such luminary. In his prayer, he says "May I be born again and again to suffer the thousands of miseries................ above all, my God the poor, my God the miserable, my God the wicked, is the sole motto of my prayer". Can the Swami's God different from mine? If not, for sure, my God is my creation, my sacred illusion!
So, the only light that exists, emanates from me, and from that light I create this universe around me.
In the same breath, Swami Chinmayananda opines that God is Brahman ब्रह्मा. But look at this, - a German research fellow, one Wilhelm Halbfass, a scientist, in his research paper, an attempt to establish the meaning of Akasha आकाशा which the later Upanishads bring in as the fifth element of matter - पंचभूत. In Chhandogya छान्दोग्य and earlier Upanishads there were only four elements - Earth, Light, Air and Fire. In his attempt to elaborate the meaning of this fifth element 'aakaasha' आकाश, he quotes quite a few verses from various Upanishads, one of which means, - 'So far as this अयं आकाश outer space (space is not an exact word for आकाश in English, there is no equivalent word) extends, thus far extends my inner space - अंतर्ह्रादयाकाश. There is everything, - that which I have, that which I do not and that I wish to have.' Halbfass further establishes, with the help of Upanishadic verses that aakasha आकाश is Brahman ब्रह्मा - universe.
If you agree with me in my inference then what I complained about Chinmayananda is right, that the only light that exists emanates from me, not my God. But I agree, this universe is not a separate entity from God. And that according to Shankaracharya, is true Vedic wisdom, when he declares अहम् ब्रहमास्मी - I am Universe or God! It is up to you to accept or reject this wisdom as real or illusory. For me, the very word 'wisdom' is creation of the mind just as every other word, to which I give meanings! Any takers?