Tax collectors were considered traitors in the days of Jesus because they were Jews who worked for the Romans and often cheated people for their own gain.
When I read about Levi being called by Jesus and how crazy this made the establishment, I'm reminded of the song, "Blackbird" by the Beatles.
Paul McCartney wrote it in 1968 in response to the racial tension going on in the United States at the time.
You were only waiting for this moment to arise.
So many people beg out of leadership in the church because they claim that they aren't good enough or don't know enough. Maybe they've forgotten the story of Levi.
Or maybe they've never heard it.