In Numbers 16 Korah along with 250 followers stepped outside their God given call. Korah was a Levite but not a priest, yet he maintained that all the children of Israel were holy and therefore fit to be priests and offer sacrifices as Aaron and his sons did ( verse 3).
Moses instructed Korah and his followers to take censers, and the following day put fire and incense in them ( verse 6 & 7), something only the priests were meant to do, and present themselves before God.
God judged them for doing this, having the earth swallow up Korah ( verse 31 & 32 ), and consuming the 250 men with fire ( verse 35) .
The censers of the 250 men were hammered into a covering on the altar, as a reminder to the children of Israel that no one but the descendants of Aaron who had been called by God to be the priests, were to come before the Lord to offer incense, as Korah and his followers had ( verse 39 & 40 ).
Paul says in Romans 12:3:
3 For I say, through the grace given to me, to everyone who is among you, not to think of himself more highly than he ought to think, but to think soberly, as God has dealt to each one a measure of faith.
Paul tells us here not to think of ourselves more highly than we ought to think, but to think soberly and see ourselves as God sees us.
We’re not to make the mistake Korah made, and step outside our God given call.