Moses and Aaron were brought again unto Pharaoh. — Moses and Aaron had uttered their threat, and had straightway left his presence. The courtiers “brought them again to Pharaoh.” The courtiers, no doubt, supposed that the king would yield; and the king was prepared to yield to a certain extent. But he had conceived of a compromise in his own mind, and this he hoped to impose upon Moses; hence his insidious question —
Who are they that shall go? — Pharaoh had not hitherto raised this question. He had known well enough that the demand extended to all the people (Exodus 8:8); but now he pretends that there had been an ambiguity, and requires that it shall be cleared up. Moses gives him an answer (Exodus 10:9) which takes away all further pretence of doubt.