Srimad Bhagavatam Canto 04, Chapter 07, Text 32

SB 4.7.32

indra uvaca
idam apy acyuta visva-bhavanam
vapur ananda-karam mano-drsam
sura-vidvit-ksapanair udayudhair
bhuja-dandair upapannam astabhih
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada: 
King Indra said: My dear Lord, Your transcendental form with eight hands and weapons in each of them appears for the welfare of the entire universe, and it is very pleasing to the mind and eyes. In such a form, Your Lordship is always prepared to punish the demons, who are envious of Your devotees.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada: 
It is generally understood from revealed scriptures that Lord Visnu appears with four hands, but in this particular sacrificial arena Lord Visnu arrived with eight hands. King Indra said, “Even though we are accustomed to see Your four-handed Visnu form, this appearance with eight hands is as real as the four-handed form.” As Lord Brahma had said, to realize the transcendental form of the Lord is beyond the power of the senses. In reply to that statement by Brahma, King Indra said that even though the transcendental form of the Lord is not perceivable by the material senses, His activities and His transcendental form can be understood. The Lord’s uncommon features, uncommon activities and uncommon beauty can be perceived even by an ordinary man. For example, when Lord Krsna appeared just like a six- or seven-year-old boy in Vrndavana, He was approached by the residents there. There were torrents of rain, and the Lord saved the residents of Vrndavana by lifting Govardhana Hill and resting it on the little finger of His left hand for seven days. This uncommon feature of the Lord should convince even materialistic persons who want to speculate to the limit of their material senses. The activities of the Lord are pleasing to experimental vision also, but impersonalists will not believe in His identity because they study the personality of the Lord by comparing their personality to His. Because men in this material world cannot lift a hill, they do not believe that the Lord can lift one. They accept the statements of Srimad-Bhagavatam to be allegorical, and they try to interpret them in their own way. But factually the Lord lifted the hill in the presence of all the inhabitants of Vrndavana, as corroborated by great acaryas and authors like Vyasadeva and Narada. Everything about the Lord — His activities, pastimes and uncommon features — should be accepted as is, and in this way, even in our present condition, we can understand the Lord. In the instance herein, King Indra confirmed: “Your presence with eight hands is as good as Your presence with four hands.” There is no doubt about it.
Srimad Bhagavatam Canto 04, Chapter 07, Text 31
Srimad Bhagavatam Canto 04, Chapter 07, Text 33