If the Mass is literally heaven on earth how can ordinary Catholics come to understand this?
Perhaps we should first ask what is the most important part that happens at Mass?
It is the words of Consecration, "This is my body... This is my blood..." Yes transubstantiation happens - when bread and wine become the body, blood, soul and divinity of Christ, what we call the Eucharist, the "Real Presence" of Christ. This is why the CCC 1324 says that The Eucharist is "the source and summit of the Christian life." - it is Christ Himself.
Also since we all are part of the mystical body (Church) of Christ - "the communion of saints"; we all celebrate the Christ's Holy Sacrifice of the Mass, this includes those in heaven - the Saints and Angels.
So if God is with us at the Mass along with the Saints and Angels where is heaven exactly? Most people have heard the saying, 'heaven is where God is'. They imply God in the spiritual form, like around us or in our hearts.., so is that heaven? This may be true in a spiritual sense, but what's the difference between spiritual sense with heaven and God at the Mass? Yes God is really present, body, blood, soul and divinity of Christ. So what does this say about this heaven.
What about heaven on earth? If we look to the Bible, it mentions several times about heaven as the throne, and earth as a footstool. One verse mentions: 'This is what the LORD says: Heaven is my throne, and the earth is my footstool. Where is the house you will build for me? Where will my resting place be?' ~ Isaiah 66:1
At Adoration we come to adore the Eucharist in the monstrance, which is called the throne for God. So heaven is the throne of Christ here on earth, and earth is the footstool. Can we make the connection now? Heaven is present at the Mass because God is present. His is present at the Mass, present in monstrance throne at Adoration, present in resting place in the tabernacle. We don't see heaven because God is veiled. We only have our faith in His Real Presence and of heaven.
Through the Holy Sacrifice of the Mass, God invites us to celebrate His great glory, in heaven on earth. We believe it! Treat the Mass, the tabernacle, the monstrance, the sanctuary with great reverence, because where God is on earth, heaven is. Literally.
Al: Catholic, learning and thankful.