Explanation:
The Veda says that God is the cause of space (Atmaana aakaashah…). The cause can be seen in its original form, only when its effect is destroyed. The lump of mud can be visualized only when the pot is destroyed. Hence, to understand the original God, space must be destroyed. When space is destroyed and does not exist, the situation is totally unimaginable, in spite of your intensive imagination even for a hundred years. Since your intelligence cannot cross space, God who is beyond space, can never be imagined by human intelligence. This is the reason for God being unimaginable.
Note:
Why does God maintain His unimaginable nature?
God is unimaginable but He enters a medium also and becomes imaginable. There are two aspects. The medium is imaginable; you can see, touch, talk, embrace, and kiss the feet of Jesus. All this is imaginable. Now the unimaginable component is homogenously mixed with the imaginable component, just like electricity in the live wire. Thus, the medium itself is God. Now God is not unimaginable; He is now imaginable through the medium. Why then is this unimaginable component retained? Suppose God were only imaginable, then everything would become known and imaginable. That would develop some negligence towards God.
Presently, you are experiencing God through the imaginable medium but you are not experiencing God directly. God is still unimaginable and by this your devotion and attraction to God is kept alive and it continues. Whenever something is known to you it will develop negligence in you. If God is completely unknown then also you will neglect God. So God should have both the aspects of known and unknown. Because God is known, you will develop devotion. However, since God is known to you, your devotion will fall after some time [1]. Then you should take the unimaginable aspect. The actual God present in this medium is still unknown. When you take the unimaginable aspect, the attraction comes alive again and negligence will disappear. To create devotion, God becomes imaginable and to continue the devotion and to avoid negligence, He is also unimaginable. Thus He is both imaginable and unimaginable. In an electric wire, you treat the wire (imaginable) as the electric current (unimaginable) since the current has pervaded over the wire. Here the current becomes imaginable. At the same time electricity remains as electricity. You have only seen the wire; the chain of metallic crystals; not the stream of electrons (electricity). So, both these concepts of imaginability and unimaginability are there to create devotion and continue the devotion respectively.
If you take Jesus, He has done unimaginable miracles that no one else can do. Don’t you think that the unimaginable component is there in Him? Yet you touch Him, talk to Him and so on. All these are imaginable components. The imaginable component attracts and the unimaginable component maintains the devotion.
[1] Due to familiarity or overfamilarity, devotion will decline.
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