In plain words
So man must not fall prey to the disease called Ahaṅkāra. Though they were Jaya and Vijaya, in the end they had to take birth as demons. The root cause of this was the Ahaṅkāra that came from being doorkeepers close to Mahāviṣṇu. Birth as a demon is the very fruit of such Ahaṅkāra. The son of that Hiraṇyakaśipu was Prahlāda. The father hated Hari. The son loved Hari. The son of this Prahlāda was Virocana. To Prahlāda, a great devotee, was born a son who was greatly wicked. The son of this Virocana was Emperor Bali. He, in turn, was a supreme devotee.
Wonderful, purifying the three worlds, sickles to the creeper of worldly life, true friends, to the forest of the sages a springtime, are the deeds of Lord Viṣṇu.
God's play cannot be described as this or that. A pure one from the womb of the wicked, a wicked one from the womb of the pure: there are many reasons for their coming in this way. In even the smallest work that God does, there is no work there without a reason. If He did not do such works, the world itself would not stand.
There is nothing, Pārtha, that I must do in the three worlds, nothing to gain that I have not gained; yet I go on in action.
If God Himself did not do such works, the world itself would waste away. It would come to a standstill. Creatures of karma who cannot see the reason keep reviling God's creation in many ways, or else criticising it. The nature of Emperor Bali is most sacred. It is divine. It is ever new. It was through the very Prema between that people and that lord that the people could not leave the lord. The lord could not leave the people. That is why Emperor Bali took Vāmana's leave and gave the people a promise. O! Beloved people! I cannot live parted from you. "You cannot live parted from me, so every year I shall come to you yourselves, to the land of Kerala, and give you darśan and go," he promised. That is this Onam. It is their belief that every year Emperor Bali appears there, in an inner way or an outer way, to visit the people of Kerala. To recognise this sacredness, this Divinity in humanness, is very hard. Who can do it? Only those who have faith in the all-knowing Divine can do it.