What does Numbers 17:21 mean?

The next day, when Moses went into the tent, he saw that Aaron's staff, the one for Levi's family, had sprouted. It had not only budded, but it had blossomed and even produced ripe almonds. Numbers 17:21 - Modern Text Bible

(Aaron's staff miraculously grows flowers and fruit overnight, proving God has chosen him and his family for the priesthood.)