Hebrews 5:7-10 (ESV)
In the days of his flesh, Jesus offered up prayers and supplications, with loud cries and tears, to him who was able to save him from death, and he was heard because of his reverence.  Although he was a son, he learned obedience through what he suffered.  And being made perfect, he became the source of eternal salvation to all who obey him,  being designated by God a high priest after the order of Melchizedek.
“He became the source of eternal salvation to all who obey him.” Again I think obey here, might be better translated listen. But still Jesus, being designated by God a high priest, is the source of eternal salvation. We need no more priests. The Order of Melchizedek is the Order that Jesus holds, he fills it. No one else has it. We listen to no one else when it comes to securing our eternal salvation, because Jesus has secured that for us.