The answer is simple, they descend to different planets in our galaxy “the Milky Way”, at the behest of Lord Krishna, God the Supreme Person, for Fulfilling the role of Messiah there, and freeing the fallen souls, who reside there.

They appear on earth for example, in different places and in various circumstances, in various climates, and thus do the good of all human beings. But apart from their divine mission, which is to remove from the illusory influence of material energy the souls embodied and conditioned by matter who live in it and thus languish in their material existence, they have nothing to do in this world. At the end of their divine mission, they return to where they came from.

God also sends down from his kingdom his pure devotees as Messiahs.

Krishna, God, the Supreme Person, himself regularly descends on a planet of a given galaxy, or send his pure devotee and authentic representative called messenger, son of God, companion or intimate servant.

By his will, the Sovereign Lord, Krishna, descends on the material planets in countless forms of Avatars for specific reasons, after which He returns to his kingdom. Avatar means “The one who descends”.

Let us know that neither the Supreme Person, nor the pure beings that He Himself sends to earth for example, are ordinary beings like the common human beings. An authentic messenger of the Lord is worth as much as God Himself.

Periodically, an envoy of the Lord appears as a ray of light, in order to teach the world the ultimate purpose of existence. Noble heads of families pray to God to entrust them with one of his envoys, so that a favorable influence may be exercised on human society.

He who accepts to place himself under the direction of such a great soul can also to access the science of God and to establish himself, just like the Pure devotee of the Lord, at the spiritual and absolute level. He will thus be freed from the grip of matter and will return to his original home, located in the kingdom of God, to benefit from eternal happiness.