As with anyone in our experience, God is unique and complex. He’s the transcendental Supreme Person, so there’s infinitely more to know about Him than anyone else. The Vedas, especially Srimad-Bhagavatam, supply detailed information about Him.
Everything about God is fully transcendental, or spiritual. Because God is absolute, there is no difference between Him and His name, form, activities, qualities, and so on. Contact with any of these gives the same spiritual benefit, namely purification of our consciousness.
The personhood of Krishna is not an idea invented by human beings naively creating a God in their own image. Nor is personhood a limiting concept when applied to God, or the Absolute Truth. As the source of everything, Krishna naturally has His own personal identity, just as each of us does. The Vedas define God as the one supreme conscious being among all other conscious beings. He is infinite, we are finite, and He maintains us all.
Naturally, the best way to understand God is to learn from Him. In the Bhagavad-gita (“The Song of God”), Lord Krishna—a real, transcendental person—tells us that He is God and reveals many things about Himself.
“Unintelligent men, who do not know Me perfectly, think that I, the Supreme Personality of Godhead, Krishna, was impersonal before and have now assumed this personality. Due to their small fund of knowledge, they do not know My higher nature, which is imperishable and supreme.”—Sri Krishna, Bhagavad-gita 7.24
Krishna is the Supreme Person, the Godhead.
Krishna is the speaker of the Bhagavad-gita, recognized throughout the world as one of mankind’s greatest books of wisdom. In the Gita, as it is also known, Krishna says repeatedly that He is God Himself, the source of everything.
Arjuna, to whom Krishna is speaking, accepts Krishna’s words as true, adding that the greatest spiritual authorities of that time also confirm that Krishna is God. Traditions that follow in the line of these authorities have carried Krishna’s teachings down to the present day.