5 Now the text changes to use a plural form of the verb. The indication is that Miriam criticized the marriage, and then the two of them raised questions about his sole leadership of the nation.
6 The use of both רַק and אַךְ (raq and ’akh) underscore the point that the issue is Moses’ uniqueness.
7 There is irony in the construction in the text. The expression “speak through us” also uses דִּבֵּר + בְּ(dibber + bé). They ask if God has not also spoken through them, after they have spoken against Moses. Shortly God will speak against them—their words are prophetic, but not as they imagined. The questions are rhetorical. They are affirming that God does not only speak through Moses, but also speaks through them. They see themselves as equal with Moses. The question that was asked of the earlier presumptuous Moses—“Who made you a ruler over us?”—could also be asked of them. God had not placed them as equals with Moses. The passage is relevant for today when so many clamor for equal authority and leadership with those whom God has legitimately called.
8 The statement is striking. Obviously the Lord knows all things. But the statement of the obvious here is meant to indicate that the Lord was about to do something about this.

In other versions

And they said, “Has the Lord indeed spoken only through Moses? Has he not spoken through us also?” And the Lord heard it.

“Has the Lord spoken only through Moses?” they asked. “Hasn’t he also spoken through us?” And the Lord heard this.

They said, “Does the Lord speak only through Moses? Does he not also speak through us?” And the Lord heard it.

They said, “Has the Lord spoken only through Moses? Hasn’t he spoken through us, too?” But the Lord heard them.

and they said, “Has Yahweh spoken only through Moses? Has not Yahweh also spoken through us?” And Yahweh heard it.

And they said, Hath the Lord indeed spoken only by Moses? hath he not spoken also by us? And the Lord heard it.

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