The Lord assured Bali Mahārāja of all protection, and finally the Lord assured him of protection from the effects of bad association with the demons. Bali Mahārāja certainly became an exalted devotee, but he was somewhat anxious because his association was not purely devotional. The Supreme Personality of Godhead therefore assured him that his demoniac mentality would be annihilated. In other words, by the association of devotees, the demoniac mentality is vanquished.

satāṁ prasaṅgān mama vīrya-saṁvido bhavanti hṛt-karṇa-rasāyanāḥ kathāḥ

( Bhāg. 3.25.25 )

When a demon associates with devotees engaged in glorifying the Supreme Personality of Godhead, he gradually becomes a pure devotee.

Thus end the Bhaktivedanta purports of the Eighth Canto, Twenty-second Chapter, of the Śrīmad-Bhāgavatam, entitled “Bali Mahārāja Surrenders His Life.”