Mark 12:25 "For when they shall rise from the dead, they neither marry, nor are given in marriage; but are as the angels which are in heaven."
The word heaven comes from the Greek word meaning "the sky; heaven as the abode of God"; by implication, "happiness; power; an eternity."
Paul mentioned being caught up into "the third heaven" in 2 Corinthians 12:2. Since "the third heaven" exists, there must also be a first and second heaven. The first is probably the atmospheric heaven, the second, the abode of supernatural angelic beings, and the third, the place where God dwells.
God now dwells in the hearts of His people, but He also sits on His throne in heaven. The Lord's commitment to dwell in us and never leave us or forsake us, must be taken as an indication of His great love for us. Heaven has a real temple which is patterned after the Old Testament tabernacle. Saints who die go immediately into heaven and into the presence of God.
Paul had a vision of heaven that made him long to go there. Most people cling to this physical life for selfish reasons. Only when we lose our life (die to self and live for Christ and others) do we truly find out what life is all about. If we seriously thought about what the scriptures teach us about our life with Christ after this physical life, we would all think like Paul. The things prepared for us are so wonderful that we can't totally comprehend them with our finite mind. We need to value our eternal life more and our temporal life less. This would solve many problems and remove a lot of grief.