On the next day Moses went into the tent of the testimony, and behold, the staff of Aaron for the house of Levi had sprouted and put forth buds and produced blossoms, and it bore ripe almonds.
Numbers 17:8 

Aaron's rod had probably been dead for many years, and well worn from use, yet God still caused it to bloom and produce ripe fruit overnight. Whatever Aaron's faults, sins, or doubts about his own abilities, God chose him to be the high priest of Israel and did it in a way that nobody else could deny.
#korach