The more I read about and reflect on our Christian faith, the more I'm convinced that life is like Jesus' pilgrimage to Jerusalem. It is an ascent to the Holy Temple where God dwells. The ascent is external and geographical: from the low-lying Sea of Galilee area (690 feet below sea level) to Mount Zion (2,500 feet above sea level.) It is also internal and spiritual: Jesus going up to his Cross out of obedience to the Father.
As Jesus' followers, our external ascent is in our journeying to the Heavenly City of Jerusalem, i.e. what people mean by "heaven." What is more important though is our "inner ascent" that is accomplished only in our acceptance of self-offering, hardships, and sacrifices, and in our willingness to go up to our cross and share the Lord's suffering and self-offering out of love.
(Inspiration: BXVI, Jesus of Nazareth, Part II, p.2.)