Those who are trying to realize the Absolute Truth are categorized according to the aspect of the Absolute Truth upon which they concentrate. Those who concentrate on Brahman, the impersonalists, are called brahmavadis. Generally, those who are trying to realize the Absolute Truth first of all realize the brahmajyoti. Those who concentrate on the Supersoul, the localized form of the Lord in the heart, called Paramatma, are known as paramatmavadis. The Supreme Lord, by His plenary portion, is sitting in everyone’s heart, and by meditation and concentration one can perceive this form. Not only is He within everyone’s heart, but He is situated also within every atom of the creation. This Paramatma realization is the second stage. The third and last stage is the realization of Bhagavan, the Supreme Personality of Godhead. Because there are three main stages of realization, the Supreme Absolute Truth is not attained in one birth. Bahunam janmanam ante. If one is fortunate, he can achieve the ultimate in one second. But generally it takes many, many years and many, many births to realize what God is.

“I am the source of all spiritual and material worlds. Everything emanates from Me. The wise who know this perfectly engage in My devotional service and worship Me with all their hearts.” (Bg. 10.8)

The Vedanta-sutra also confirms that the Absolute Truth is He from whom everything is born. If we truly believe that Krsna is the origin of everything, and if we worship Him, our whole account is closed in one second. But if one doesn’t believe and says, “Oh, I want to see what God is,” he has to go by stages by realizing the impersonal Brahman effulgence and then Paramatma, the localized feature, before finally coming to the last stage of realizing, “Oh, here is the Supreme personality of Godhead.” It should be understood, however, that this process takes more time. When one through many years of research comes to realize the Absolute Truth, he concludes vasudevah sarvam iti–”Vasudeva is all that is.” Vasudeva is a name for Krsna, and it means “He who lives everywhere.” Realizing that Vasudeva is the root of everything–mam prapadyate–he surrenders. The surrendering process is the ultimate goal; either one does it immediately or after many births of research work. In either case, surrender must be there by realizing that “God is great, and I am His subordinate.”

Understanding this, the wise man will surrender immediately and not wait to take many, many births. He understands that this information is given by the Supreme Lord out of His infinite mercy on the conditioned souls. We are all conditioned souls, suffering the threefold miseries of this material world. Now the Supreme Lord is giving us the opportunity to escape these miseries by the surrendering process.
~ On the Way to Krsna, Chapter 5, “Steering Toward the Supreme