Who was the greatest priest?

There have been thousands of truly great priests who have sacrificed so much to be able to serve God's Church and spread the truth of Jesus Christ throughout the world, over the past 20 centuries.

Jesus Christ. Without a doubt.

Jesus Christ is our Great High Priest perfected forever (Hebrews 7:28) and instead of His priesthood having to come to an end like man's does when they die physically, Jesus Christ has an unchangeable and living priesthood for ever, after the order of Melchizedek who was without beginning or end.

Judas Priest would be my vote.

The only religion of GOD promote mankind to have families , then those people who are fathers, mothers and their children who believe in GOD and practice as according to HIS commands, then would be the greatest people in the sight of GOD, so his /her as being father and mother , when perform one good deed , then GOD promise to reward them with 10 folds of goodness or even more. The person who bring the food to feed a person who pray in the Mosque, GOD would reward that former person more. So I have not seen in any scriptures of GOD that HE order people to become priest or nun, or to set up churches or temples for them.  So do not mind about being the greatest priest in the sight of GOD, the Lord of all the worlds.

Jesus Christ himself is the highest priest in the order of Melchizedek, as it is written in 

Heb 5:8-10 Son though he was, he learned obedience from what he suffered and, once made perfect, he became the source of eternal salvation for all who obey him and was designated by God to be high priest in the order of Melchizedek. 

To know about the other of  Melchizedek, please contact your nearest preist or preacher from The Church of God World mission society.  

I would put St. Ignatius, Nicolaus Copernicus, George’s Lemaitre, and Gregor Mendel on any such list. You know the ones who contributed to science and whose ideas were shunned or still are today because they contradict Church doctrine. 

Heliocentrism, the Big Bang, and the very genetics that form the basis of evolution - so heretical, so profound. 

Jesus Christ, Son of God and high-priest of God.

All of the dead ones are tied for first place.

What would constitute a 'great' priest?