Now a high priest is a man chosen to represent other human beings in their dealings with God. He presents their gifts to God and offers their sacrifices for sins.
And because he is human, he is able to deal gently with the people, though they are ignorant and wayward. For he is subject to the same weaknesses they have.
That is why he has to offer sacrifices, both for their sins and for his own sins.
And no one can become a high priest simply because he wants such an honor. He has to be called by God for this work, just as Aaron was.
That is why Christ did not exalt himself to become High Priest. No, he was chosen by God, who said to him, "You are my Son. Today I have become your Father."
References for Hebrews 5:5
And in another passage God said to him, "You are a priest forever in the line of Melchizedek."
References for Hebrews 5:6
While Jesus was here on earth, he offered prayers and pleadings, with a loud cry and tears, to the one who could deliver him out of death. And God heard his prayers because of his reverence for God.
So even though Jesus was God's Son, he learned obedience from the things he suffered.
In this way, God qualified him as a perfect High Priest, and he became the source of eternal salvation for all those who obey him.
And God designated him to be a High Priest in the line of Melchizedek.
There is so much more we would like to say about this. But you don't seem to listen, so it's hard to make you understand.
You have been Christians a long time now, and you ought to be teaching others. Instead, you need someone to teach you again the basic things a beginner must learn about the Scriptures. You are like babies who drink only milk and cannot eat solid food.
References for Hebrews 5:12
And a person who is living on milk isn't very far along in the Christian life and doesn't know much about doing what is right.
Solid food is for those who are mature, who have trained themselves to recognize the difference between right and wrong and then do what is right.