One of the most powerful scenes in Revelation is the moment when the Lamb takes the scroll from the right hand of the one who sits on the throne. His achievement is celebrated by heaven’s citizens like this:
When he took it, the four living creatures and the twenty-four elders fell down before the Lamb. Each of the elders held a harp and gold bowls filled with incense, which are the prayers of the holy ones. 9 They sang a new hymn: “Worthy are you to receive the scroll and to break open its seals, for you were slain and with your blood you purchased for God those from every tribe and tongue, people and nation. 10 You made them a kingdom and priests for our God, and they will reign on earth.”
Have a a second look at the criteria for priestly status. In Revelation’s world, that status comes as a result of the sacrifice of the Lamb. Note especially the absence of any mention of race and gender.
And have nice MLK Day!