Explanation:
When the Veda says that you are Brahman, we can take it in the usual sense as said above [1]. Brahman stands for the soul and therefore, the soul present even in an ignorant person like Svetaketu, is not an exception to this concept. Alternatively, we can take another angle also, in which the father is blessing his son (Svetaketu) due to excess of love, so that the ignorant soul is blessed to become God by becoming a Human Incarnation in the very near future. Here the verb is in the present tense (“You are That”). The present tense of a verb can be used to mean the immediate future in a blessing. For example, if I say, “You are going”, it could mean that you are going to go very shortly. This angle is also good since it reflects the blessing of the father in which his excess love is exhibited.
Note:
The immediate future can be expressed in projection by the use of the present tense. Suppose I say “I am going”, it means that I will go shortly. The immediate future is expressed in the present tense clause. The father is giving a blessing to his son that his son will become a liberated soul by spiritual effort or sadhana, and he will be selected by God as a Human Incarnation to enter this world. In the Human Incarnation, the soul is treated as God. He is giving a blessing to his son to rise to that level. He wants his son to get the grace of God as early as possible. Present tense here refers to the immediate future. This shows how much the father loved the son.
The first interpretation of this Mahavakya that any soul, being the greatest created item, is Brahman. This coincides with other two Mahavakyas, “My soul is the greatest (Aham Brahmasmi)” and “His soul is the greatest (Ayamatma Brahma)”. The soul in me, you and him is treated as the greatest and is given the word Brahman. The second interpretation is also possible. One can enjoy this second one also, in which a particular soul might be selected by God to enter this world. In that case the soul will be treated as God. If the contradiction is removed by the first explanation, the second interpretation is not needed.
[1] The soul is Brahman since it is the greatest of created items.
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