SB 8.19.18
sri-balir uvaca
aho brahmana-dayada
vacas te vrddha-sammatah
tvam balo balisa-matih
svartham praty abudho yatha
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Bali Maharaja said: O son of a brahmana, Your instructions are as good as those of learned and elderly persons. Nonetheless, You are a boy, and Your intelligence is insufficient. Thus You are not very prudent in regard to Your self-interest.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
The Supreme Personality of Godhead, being full in Himself, actually has nothing to want for His self-interest. Lord Vamanadeva, therefore, had not gone to Bali Maharaja for His own self-interest. As stated in Bhagavad-gita (5.29), bhoktaram yajña-tapasam sarva-loka-mahesvaram. The Lord is the proprietor of all planets, in both the material and spiritual worlds. Why should He be in want of land? Bali Maharaja rightly said that Lord Vamanadeva was not at all prudent in regard to His own personal interests. Lord Vamanadeva had approached Bali not for His personal welfare but for the welfare of His devotees. Devotees sacrifice all personal interests to satisfy the Supreme Personality of Godhead, and similarly the Supreme Lord, although having no personal interests, can do anything for the interests of His devotees. One who is full in himself has no personal interests.