‘And Yahweh spoke suddenly to Moses, and to Aaron, and to Miriam, “Come out you three to the tent of meeting.” And they three came out.'
Then Yahweh called Moses, Aaron and Miriam to come out to the Tent of meeting. It was seemingly ‘out of the blue'. None would know the reason for the call, and Aaron and Miriam probably initially had a feeling of satisfaction that the fact that they were all being called together was proving them right. Did it not demonstrate that God did see them as on a par with Moses? So the three ‘came out'