Numbers 12:1

Then Miriam and Aaron spoke against Moses because of the Ethiopian woman whom he had married; for he had married an Ethiopian woman.

Surrounding context

12:1 Then Miriam and Aaron spoke against Moses because of the Ethiopian woman whom he had married; for he had married an Ethiopian woman.

12:2 So they said, "Has the LORD indeed spoken only through Moses? Has He not spoken through us also?" And the LORD heard it.