Jesus Christ was willing to admit every good man to the family of God. It is not the man who believes a certain something, but the man who does the will of the Father in heaven, who is right. On this basis-being right and doing right-the whole world can unite.
This is the great lesson that we are here to learn through myriads of births and heavens and hells - that there is nothing to be asked for, desired for, beyond one's spiritual Self (atman).
Infinite perfection is in every man, though unmanifested. Every man has in him the potentiality of attaining to perfect saintliness, Rishihood, or to the most exalted position of an Avatâra, or to the greatness of a hero in material discoveries.