In this clip from a talk with students in the Torrey Honors College at Biola University in 2012, Randy says that the nature of the the New Earth is physical. He explains that some theologians say the present Heaven is completely immaterial, but he points to examples in Scripture that support the physicality of the present Heaven.
What Is the Difference between the Terms Heaven and the New Earth?
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In this clip from a talk with students in the Torrey Honors College at Biola University in 2012, Randy explains that Heaven is the central dwelling place of God, where His throne is. But one day, God will bring Heaven down to the New Earth to dwell with His people.