The others who became priests are numerous because death prevented them from continuing to serve.
In contrast, he holds the office of priest permanently because he continues to serve forever.
This is why he can completely save those who are approaching God through him, because he always lives to speak with God for them.
It's appropriate for us to have this kind of high priest: holy, innocent, incorrupt, separate from sinners, and raised high above the heavens.
He doesn't need to offer sacrifices every day like the other high priests, first for their own sins and then for the sins of the people. He did this once for all when he offered himself.
The Law appoints people who are prone to weakness as high priests, but the content of the solemn pledge, which came after the Law, appointed a Son who has been made perfect forever.