SB 6.9.47
sri-bhagavan uvaca
prito ’ham vah sura-srestha
mad-upasthana-vidyaya
atmaisvarya-smrtih pumsam
bhaktis caiva yaya mayi
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
The Supreme Personality of Godhead said: O beloved demigods, you have offered your prayers to Me with great knowledge, and I am certainly most pleased with you. A person is liberated by such knowledge, and thus he remembers My exalted position, which is above the conditions of material life. Such a devotee is fully purified by offering prayers in full knowledge. This is the source of devotional service to Me.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Another name of the Supreme Personality of Godhead is Uttamasloka, which means that He is offered prayers with selected verses. Bhakti means sravanam kirtanam visnoh, chanting and hearing about Lord Visnu. Impersonalists cannot be purified, for they do not offer personal prayers to the Supreme Personality of Godhead. Even though they sometimes offer prayers, the prayers are not directed toward the Supreme Person. Impersonalists sometimes show their incomplete knowledge by addressing the Lord as being nameless. They always offer prayers indirectly, saying, “You are this, You are that,” but they do not know to whom they are praying. A devotee, however, always offers personal prayers. A devotee says, govindam adi-purusam tam aham bhajami: “I offer my respectful obeisances unto Govinda, unto Krsna.” That is the way to offer prayers. If one continues to offer such personal prayers to the Supreme Personality of Godhead, he is eligible to become a pure devotee and return home, back to Godhead.