Answer
There are broadly three ways in which a person can see the deity.
First, one sees only what the physical eyes perceive — just stone. Such a person is seeing only the material energy. From this perspective, the deity appears to be nothing more than matter.
Second, a person understands the principle of archa-vigraha. He knows that the Lord mercifully accepts a form similar to the deity and manifests within it. When the Lord enters matter, He does not come alone — He comes with all His shaktis. By His presence, the material elements are fully spiritualized. What appeared as matter is no longer ordinary matter; it becomes fully empowered. Such a person still sees the external form, but understands that it is infused with the Lord’s full potency and presence. For him, the deity is as good as the sat-cit-ananda vigraha of the Lord.
Third, at a higher level of realization, one no longer sees any material element at all. The deity is directly perceived as sat-cit-ananda — pure spiritual existence, consciousness, and bliss. The Lord Himself is fully present there. The “body” of the deity is not material; it is spiritual energy. The Lord, in that form, is non-different from Himself.
An example can help. When one approaches a pure devotee, one bows and touches his feet. At that moment, one does not think, “I am touching flesh and bone.” Rather, one feels they are touching something sacred. Even a great soul like A. C. Bhaktivedanta Swami Prabhupada allowed devotees to touch his feet, not because he identified with the body, but because that body was fully engaged in divine service and thus spiritually potent.
If even a pure devotee’s body is honored in this way, then what to speak of the Lord Himself? The Lord, being absolute, can fully identify with His deity form. Just as conditioned souls mistakenly identify with the body, the Lord, by His absolute potency, can perfectly manifest Himself in the deity form. Therefore, there is no difference between the Lord and the deity.
From the highest vision, there is no matter there at all — only God is present.
However, this realization comes progressively.
First, one sees matter.
Then, with shraddha (faith), one understands it is not ordinary matter.
Through worship, one becomes purified.
As purification deepens, the spiritual mind awakens.
Only then can one truly perceive the sat-cit-ananda nature of the deity.
In the same way, the full experience of the Hare Krishna maha-mantra is also revealed only through purification.
So, realization is gradual — step by step, through sincere practice and inner purification.