invisible

You rascal, You have been nourished by our enemies to kill us, and You have killed some demons by remaining invisible. O fool, Your power is only mystic, so today I shall enliven my kinsmen by killing You.

Purport: 

The demon used the word abhavāya, which means “for killing.” Śrīdhara Svāmī comments that this “killing” means liberating, or, in other words, killing the process of continued birth and death. 

The Lord kills the process of 

1. birth and 
2. death and keeps Himself invisible. 

The activities of the Lord’s internal potency are inconceivable, but by a slight exhibition of this potency, the Lord, by His grace, can deliver one from nescience. Śucaḥ means “miseries”; the miseries of material existence can be extinguished by the Lord by His internal potency, yoga-māyā.

In the Upaniṣads (Śvetāśvatara Upaniṣad 6.8) it is stated, parāsya śaktir vividhaiva śrūyate. The Lord is invisible to the eyes of the common man, but His energies act in various ways. When demons are in adversity, they think that God is hiding Himself and is working by His mystic potency. They think that if they can find God they can kill Him just by seeing Him. Hiraṇyākṣa thought that way, and he challenged the Lord: “You have done tremendous harm to our community, taking the part of the demigods, and You have killed our kinsmen in so many ways, always keeping Yourself hidden. Now I see You face to face, and I am not going to let You go. I shall kill You and save my kinsmen from Your mystic misdeeds.”

Not only are demons always anxious to kill God with words and philosophy, but they think that if one is materially powerful he can kill God with materially fatal weapons. Demons like Kaṁsa, Rāvaṇa and Hiraṇyakaśipu thought themselves powerful enough to kill even God. Demons cannot understand that God, by His multifarious potencies, can work so wonderfully that He can be present everywhere and still remain in His eternal abode, Goloka Vṛndāvana.

http://www.vedabase.com/en/sb/3/18/4