Moses spoke to Korah and to all his community, saying, "In the morning, the LORD will make known who is His…Why wait until the morning? Because things always look different in the light of day. Moses hoped, explains Rashi, that by morning, Korah and his band of followers would retract their claim. The Netziv points out that in Hebrew the word for morning – boker, is related to the word for criticism – bikoret. If a person must take a critical look at something, it's best to sleep on it and wait until the morning.