It is primarily God’s dwelling place in the biblical tradition: a parallel realm where everything operates according to God’s will. Heaven is a place of peace, love, community, and worship, where God is surrounded by a heavenly court and other heavenly beings.

Biblical authors imagined the earth as a flat place with Sheol below (the realm of the dead) and a dome over the earth that separates it from the heavens or sky above. Of course, we know the earth is not flat, and this three-tiered universe makes no sense to a modern mind. Even so, the concept of heaven (wherever it is located) continues in Christian theology as the place where God dwells and a theological claim that this world is not all that there is.

The other main metaphor for God’s dwelling place in the Bible is paradise. According to Luke’s version of the crucifixion, Jesus converses with the men on either side of him while waiting to die and promises the man on a neighbouring cross “today you will be with me in paradise”.

References to paradise in the Bible are likely due to the influence of Persian culture and particularly Persian Royal gardens (paridaida). Persian walled gardens were known for their beautiful layout, diversity of plant life, walled enclosures, and being a place where the royal family might safely walk. They were effectively a paradise on earth.

The garden of Eden in Genesis 2 is strikingly similar to a Persian Royal garden or paradise. It has abundant water sources in the rivers that run through it, fruit and plants of every kind for food, and it is “pleasing to the eye”. God dwells there, or at least visits, and talks with Adam and Eve like a King might in a royal garden.

We can't get to heaven by works, because God doesn't pick favorites. To be accepted into heaven you must admit you're a sinner, ask for forgiveness, admit that Jesus died for your sins and rose again, and ask Him to have a relationship with you. Jesus is a mystery and we won't know everything until we get to heaven.