One yuga means about 4,300,000's of years. 4,300,000's of years, that makes a complete yuga. Such seventy-one yuga is the duration of a Manu. That is called Man . . . and each Manu is also an incarnation, manvantarāvatāra. And such Manu takes place, fourteen Manus take place, during one day of Brahma. So manvantarāvatāra.
Then yuga avatāra. Yuga avatāra . . . in each yuga, during that 4,300,000's of years, there are yuga avatāra. They are the incarnation. They come. They are called yugāvatāras. And then there is śaktyāveśa-avatāra. Śaktyāveśa-avatāra, they are counted just like Lord Buddha, Jesus Christ. They are counted amongst the śaktyāveśāvatāras. They are also incarnation of śaktyāveśāvatāra, powerful. In this way the Supreme Lord manifests all over the universes. There are innumerable universes, and some of His incarnation are working always.
So God's kingdom is not vacant. Just like we are thinking that except this earthly planet, all planets are vacant. Somebody is suggesting it is a lump of ashes. Just like they are thinking of this moon planet—a lump of dust. I cannot, of course, think like that. How dust can remain in a lump and how so much illumination come out from the dust? But they are putting the theory that the moon planet is a lump of dust. So let them do. But from the scripture we understand that there are innumerable universes, and each and every universe is full with innumerable planets, and each planet is full with innumerable living entities, and God's incarnation is working somewhere, other, to reclaim these conditioned souls.