*Minor differences ignored. Grouped by changes, with first version listed as example.
For they grieved his spirit The verb mrh, marah, properly signifies to vex or irritate, but as it is here put in what the Hebrews call the Hiphil conjugation, some are of opinion that it is to be understood passively, to denote that it was the people who were the occasion of the rebellion; which interpretation does not appear to me to be very objectionable. I cannot, however, agree with those who would have the particle 't, eth, to be a sign of what is denominated the dative case, as if Moses might be said to have rebelled against the Spirit of God. Had he done so, then assuredly the prophet would not have spoken so severely of the sin and folly into which he had inadvertently fallen. The meaning which I have already given answers very well, That the prime movers of the rebellion must have committed a very heinous offense, seeing that Moses, who had been pushed on by the impetuosity of the people to sin, was so severely dealt with by God. But while the prophet informs us that Moses was punished on the people's account, he is not to be understood as saying that he was altogether blameless. For even admitting that his spirit was ruffled in consequence of the tumult of the people, this ought to have made him the more careful to continue steadfast in his adherence to the Law of God. He adds, that he spoke with his lips; and this I take to refer to Moses, there being no ground for the conjecture that it refers to the punishment which God expressly denounced against Moses. It is more likely that these words were intended by the prophet to express how greatly the spirit of Moses was agitated when he openly murmured against God. The prophet, therefore, informs us that the submissive and gentle spirit of Moses was fanned, as it were, into a breeze by the perverseness of the people, so that even he spake un-advisedly, saying, "Can God give you water out of the rock?" (Numbers 20:10) For such was the indignation which he felt burning within him, that he could not calmly wait for the commandment of God to smite the rock.
Because they provoked his spirit - literally, "They made his spirit bitter," or they embittered his soul. They threw him off his guard, so that instead of manifesting the meekness and gentleness which so eminently characterized him in general (see Numbers 12:3), he gave way to expressions of anger. See Numbers 20:10.
So that he spake unadvisedly with his lips - Passionately; in a severe, harsh, and threatening manner. He did not bear with them as he should have done; he did not refer to God, to his power, and to his goodness as he should have done; he spake as if the whole thing depended on him and Aaron: "Hear now, ye rebels; must we fetch you water out of this rock?" The word rendered "spake unadvisedly" - בטא bâṭâ' - means properly to "babble;" and then, to talk idly, or unadvisedly; to utter that which has no meaning, or an improper meaning. Let us not harshly blame Moses, until we are placed in circumstances similar to his, and see how we would ourselves act. Who is there that would not have been provoked as he was, or even to a greater degree? If there are any such, let them "cast the first stone."
They provoked his spirit - המרו himru, from מרה marah, to rebel: they brought it into a rebellious state; he was soured and irritated, and was off his guard.
So that he spake unadvisedly with his lips - For this sentence we have only these two words in the Hebrew, ויבטא בשפתיו vayebatte bisephathaiv, he stuttered or stammered with his lips, indicating that he was transported with anger. See the notes on Numbers 20:10-12 (note).
Because they provoked his spirit;.... Though he was a very meek man, meeker than any upon the face of the earth, Numbers 12:2, yet, being greatly provoked, let fall some passionate and undue expressions: and this was not only his sin, but the fault of those also that provoked him, and with this view it is mentioned. The Targum is,
"for they rebelled against his Holy Spirit;''
the Holy Spirit of God, as in Isaiah 63:10. Jarchi interprets it of Moses and Aaron provoking the Spirit of God; which sense is mentioned, by Aben Ezra and Kimchi; though they seem to prefer the former, and which seems best. Some interpret it of the Israelites, that they caused Moses and Aaron to provoke his Spirit.
So that he spake unadvisedly with his lips; that is, Moses spake,
saying, Hear now, ye rebels, must we, or "can we",
fetch you water out of this rock? Which words were spoken in an angry passionate way, calling them rebels, and expressing diffidence about getting water out of the rock; which was the thing that was so displeasing to God, because they did not believe him to sanctify him in the eyes of the children of Israel, Numbers 25:10. Jarchi, as before, understands this of God, of his speaking, pronouncing, and declaring, that Moses and Aaron should not bring the congregation into the land of Canaan, Numbers 25:18, and so the word "unadvisedly" may be left out, and only read, "he spake with his lips"; but the other sense is to be preferred.
*More commentary available at chapter level.