Hebrews 5:5-6

5It is the same with Christ. He did not choose himself to be God's special priest. He did not choose to make himself important like that. God chose him. God showed that Christ was very important. God said to him: ‘You are my Son. Today I have become your Father.’

6And in another place in the Bible God says this: ‘You will be a priest for ever, in the same way that Melchizedek was a priest long ago.’