When Jesus returns and gathers all the redeemed of all the ages, heaven will be filled.

         On the right hand will also be Gabriel and his messengers.

         On the left will be Michael and his warriors

         Before the throne will be all of the redeemed.

         Lucifer and his demons will be locked up for 1,000 years. 

That is when the first 1,000 years [Christ's millennial reign] will begin.