What does the Bible teach concerning Heaven?

It really depends on how we define heaven. Heaven is not so much a place, as it is a "presence". What I mean by this, is that heaven is only paradise because it is filled entirely with God's presence. If we talk about heaven in reference to the place we go immediately when we die (the intermediate state) that specific "place" is not our final destination. The Bible teaches that the new earth will be our final resting place. We will receive new resurrected bodies there and will live Christ and fellow believers forever. Heaven is NOT a place "in the sky", nor is it a place where "people sing all the time". The majority of Christians DO NOT believe these things. When the Bible speaks of heaven and hell, it uses metaphorical language to help us understand them better. That is why we are met with "streets of gold" in reference to heaven (timelessness) and "unquenchable fire" in reference to hell (no presence of God). Most humans have difficulties grasping these spiritual concepts, therefore the Bible uses these pictures to help us understand these two places.