Every high priest is chosen from the people and is appointed to work for the people as they relate to God. He presents to God both their gifts and sacrifices for their sins. The high priest understands how ignorant and deluded people feel because he also experiences the same kind of human weaknesses. As a result he has to offer sacrifices for his sins as well as for those of the people. No one can take the position of high priest for himself; he must be chosen by God, just like Aaron was. In just the same way Christ did not honor himself by becoming high priest. It was God who said to him, “You are my Son. Today I have become your Father.”* In another verse, God says, “You are a priest forever, following the order of Melchizedek.” Jesus, while he was here in human form, prayed and appealed with loud cries and tears to God, the one who was able to save him from death. Jesus was heard because of his respect for God. Even though he was God's Son, Jesus learned through suffering what obedience really means. When his experience was complete,§ he became the source of eternal salvation to everyone who does what he says, 10 having been designated by God as a high priest according to the order of Melchizedek.
11 We have much to say about Jesus, and it's hard to explain because you don't seem able to understand! 12 By now you should have had enough time to become teachers, but you need someone to teach you the fundamentals, the first principles of God's word. It's like you need to go back to baby milk instead of solid food! 13 Those who drink baby milk don't have the experience of living the right way—they're just babies. 14 Solid food is for grown-ups—those who by always using their brains have learned to tell the difference between good and evil.
* 5:5 Quoting Psalms 2:7 5:6 Quoting Psalms 110:4 5:8 The usual translation that Jesus “learned obedience through suffering” could suggest that Jesus was not originally obedient, or that suffering was necessary in order for him to learn—both rather strange ideas to place on Jesus, the pre-existing Son of God. The thought here appears to be that even though Jesus was God's Son, his earthly expereince demonstrated the cost and consequences of obedience. In some ways this parallels Jesus request to have the cup of suffering taken away from him, but then he surrenders his will in obedience to his Father. See Matthew 26:39. § 5:9 Avoiding the term “having been made perfect,” which in the minds of some might suggest he wasn't perfect in the first place.