Exodus 2:14

And he said, who made thee a prince and a judge over us?
&c.] God had designed him for one, and so he appeared to be afterwards; but this man's meaning is, that he was not appointed by Pharaoh's order then, and so had nothing to do to interfere in their differences and quarrels; though Moses did not take upon him to act in an authoritative way, but to exhort and persuade them to peace and love, as they were brethren:

intendest thou to kill me, as thou killedst the Egyptian?
if this was Dathan, or however the same Hebrew that he had defended and rescued from the Egyptian, it was very ungenerous in him to upbraid him with it; or if that Hebrew had made him his confident, and acquainted him with that affair, as it was unfaithful to betray it, since it was in favour of one of his own people, it was ungrateful to reproach him with it:

and Moses feared;
lest the thing should be discovered and be told to Pharaoh, and he should suffer for it: this fear that possessed Moses was before he fled from Egypt, and went to Midian, not when he forsook it, and never returned more, at the departure of the children of Israel, to which the apostle refers, ( Hebrews 11:27 ) and is no contradiction to this:

and said, surely this thing is known;
he said this within himself, he concluded from this speech, that either somebody had seen him commit the fact he was not aware of, or the Hebrew, whose part he took, had through weakness told it to another, from whom this man had it, or to himself; for by this it seems that he was not the same Hebrew, on whose account Moses had slain the Egyptian, for then the thing would have been still a secret between them as before; only the other Hebrew this was now contending with must hereby come to the knowledge of it, and so Moses might fear, that getting into more hands it would come out, as it did; (See Gill on Acts 7:27). (See Gill on Acts 7:28). (See Gill on Acts 7:29).