Allah states that Messengers have been despatched to them confirming that which they by now realized from their scriptures. A different probability is there are 4 separate realms with the blessed, of which possibly Firdaws or Eden could be the uppermost. This is based on Surah 55, If not, merely https://stephennrtuv.bloggazzo.com/30030019/jannah-firdaus-an-overview