This is a perplexing question. Remember, there are two heavens described
in the Bible – the one you would go to now if you died and the one that will be
created for all believers throughout eternity.
The first is a spiritual place where your spirit lives in God’s
presence.
The second will be a physical, created place where you live with God
in your resurrected body. We will talk about the second, future heaven since
the first cannot be measured since it exists in a dimension not measured by a
tape measure.
The second heaven, much like our own universe, will have an almost
limitless boundary. That heaven is a
created place so it exists within a dimensional reality. In Revelation 21, the
city is even measured by length and width, showing us that heaven has a
physical quality.
However, on the other hand, it is the place where God lives
forever, so it must contain His eternal quality.
The universe was always meant to be a physical reminder of the
eternal nature of God, so the expanse of heaven should drive us to only one
answer.
How far does heaven stretch?
God.