It is said if you have to ask you are not of of the 144000. It is known who the 144000 is. It is recorded, and when almost all of them are in heaven, that is when the dead will rise from the graves in search of there families, and we will have Paradise on Earth. These people left was born before 1914. This is what I was taught. Also these were the only people that participated in communion at passover once a year.