In plain words
The fourth is Pradyumna. Pradyumna means that there is no one in the world who can master Him or conquer Him. In the world He alone is His own equal. He alone is supreme in Himself. There is no one lower than Him and no one higher. The reason is that He is present even in those who are lower. This Pradyumna-nature has spread through everything, evenly. The oneness of these four is humanness. God is not separate from man. Vāsudeva: the Paramātma. Saṅkarṣaṇa: the jīvātma. Pradyumna: Manas. Aniruddha: Aham. The oneness of these four is humanness. If any one of these four were missing, no one could live in this world. Then you may ask, must Ahaṅkāra too be there? Aham must be there. But Ahaṅkāra must not be there. Aham means “I”. Do not think that the form is “I”. Ahaṃ brahmasmi. I am not the body. I am not “I am the jīva”. Aham. Aham. In Sanskrit, it begins with the letter called a. At the end comes the letter ha. When the a at the beginning and the ha at the end come together, it becomes aham. All the other sounds lie merged in these two. Aham means the principle that pervades from the atom to Brahman. That is why the mahāvākya says, “Ahaṃ brahmasmi.” Prajñānaṃ brahma. That Prajñāna am I. Tattvamasi: That am I. Unable to recognise the meaning of such mahāvākyas, man takes the body alone, impermanent and transient, to be eternal, and falls into sorrow. The one form of these four mahāvākyas is God.
No one tries to recognise the meaning held in this word Bhagavān. Bhaga means sambharta. Second, it means bharta. To create, taking this world as the base, is sambharta. Taking Prakṛti as the base, God creates. Mixing earth and water, the potter makes pots. Without water, or without earth, he cannot create pots. Water and earth are the base of the pot. Creation happens only when two of these five elements come together. Yet those two substances, too, are His own forms. How wondrous! He gave the wind the power to put out the lamp. He gave the lamp the power to drive away darkness. If that same wind blows on this same lamp, the lamp cannot stay. They are the powers of one and the same God. One puts out the other. The two are one, are they not! If you ask why He gave the one the power to put out, the power to put out is its own. The power to be put out is the other's. God's creation holds an inner meaning that cannot be understood. Taking Prakṛti as the base, God creates. That is why they called Him sambharta. The one who protects what has been created is bharta. Bha means radiance. Ga means to spread. Vantuḍu means one who is able, one who is powerful. Bhagavān means the one who is able to spread light.