so Priest on earth can do much greater work then people in heaven since they celebrate Mass on earth?
It’s not a question of greater. It’s different.
The Mass is the greatest prayer that the Church has, the greatest act of Worship that we can offer here on Earth. The priest stands as the person of Christ. When we offer our prayers at Mass and have a Mass “Said” for someone, the Mass is offered on their behalf, and all of our prayers as the Body of Christ (the Church) are joined with It.
It is said that the angels and saints rejoice when Mass is said, and if we were able to “See” what was really happening at Mass, we would see the cherubim and seraphim attending the Mass themselves, surrounding the altar.
The saints’ prayers are very powerful. They are part of the Communion of Saints, which is part of the Body of Christ, the living and the dead. They are, in deed, powerful as they are in heaven and are joined in union with God.
The Act of the Mass, though, brings Heaven to Earth…brings Christ’s Body and Blood within our very midst. The priest is not doing the “work”…God is. Through the priests’ ordination, he is given this awesome responsibility. This was given when Jesus said to Peter that what he bound on earth would be bound in heaven, etc., and when He asked the apostles to “Do this in memory of Me” at the Last Supper.
I suggest that you read through the Catechism of the Catholic Church, or the Baltimore Catechism (an older version, but I enjoy it, and it’s still valid.) to get a straightforward and clearer view of these teachings, starting at the beginning. You can’t run until you can walk, as the saying goes, so you might want to brush up on the basic doctrines first as these can be a little difficult to wrap your mind around without the solid foundational teachings of the Church being learned first.
God Bless You.