The word avitatha-girbhih means they whose spoken vibrations cannot be nullified. The brahmanas (dvija, the twice-born), are given a chance by the sastric regulations to become almost as powerful as the Supreme Lord. Whatever a brahmana speaks cannot be nullified or changed in any circumstance. According to the Vedic injunctions, a brahmana is the mouth of the Supreme Personality of Godhead; therefore in all rituals a brahmana is offered food (brahmana-bhojana) because when a brahmana eats, it is considered that the Supreme Lord Himself eats. Similarly, whatever a brahmana speaks cannot be changed. It must act. The learned sages who were priests at Maharaja Nabhis sacrifice were not only brahmanas but were so qualified that they were like devas, demigods, or God Himself. If this were not the case, how could they invite Lord Visnu to come to the sacrificial arena? God is one, and God does not belong to this or that religion. In Kali-yuga, different religious sects consider their God to be different from the God of others, but that is not possible. God is one, and He is appreciated according to different angles of vision. In this verse the word kaivalyat means that God has no competitor. There is only one God. In the Svetasvatara Upanisad (6.8) it is said, na tat-samas cabhyadhikas ca drsyate: No one is found to be equal to Him or greater than Him. That is the definition of God.