“For we know that if the tent that is our earthly home is destroyed, we have a building from God, a house not made with hands, eternal in the heavens.” (2 Corinthians 5:1)
What Paul is telling us is that this earthly body which we hold onto so dearly is not permanent. Human life is like a tent, temporary, vulnerable, and susceptible to the weather and dangers of all sorts. Eternal life is like a building, but one that is indestructible, beautiful and permanent. When we die, we lose the tent but we are not left homeless. The tent, our body we call home now, will be destroyed only to be replaced by our glorified body. The loss of one is followed directly by the ownership of the other which is far superior to what we cherish so dearly now.
And often we do cherish this body and this life too much, so much so that we think this life is all that is solid and real. When we look at heaven we see it as shadowy, vague and insubstantial. But Paul is telling us that the reverse is true. The life to come is intense, permanent and real, while this earthly life is fragile, temporary and inadequate. Deep down the Spirit of God who lives within each believer comforts us in the midst of pain, suffering and mortality. He tells us that eternal life in heaven is the reality, a sure and certain hope that enables us to persevere.