You answered them, O LORD our God: you were a God that forgave them, though you took vengeance on their wrongdoings.
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Augustine of Hippo
9. "Moses and Aaron among His priests, and Samuel among such as call upon His Name: these called upon the Lord, and He heard them" (ver. 6). "He spake unto them out of the cloudy pillar" (ver. 7). ...Of Moses it is not there stated that he was a priest. But if he was not this, what was he? Could he be anything greater than a priest? This Psalm declareth that he also was himself a priest: "Moses and Aaron among His priests." They therefore were the Lord's priests. Samuel is read of later in the Book of Kings: this Samuel is in David's times; for he anointed the holy David. Samuel from his infancy grew up in the temple. ...He mentioneth these: and by these desireth us to understand all the saints. Yet why hath he here named those? Because we said that we ought here to understand Christ. Attend, holy brethren. He said above, "O magnify the Lord our God: and fall down before His footstool, for He is holy:" praising some one, that is, our Lord Jesus Christ; whose footstool is to be worshipp...
All their inventions. That is, all the enterprizes of their enemies against them, as in the case of Core, Dathan, and Abiron. (Challoner) (Numbers xvi.) (Worthington) Syriac, "injuries. "The failings of these great men were punished in mercy. (Calmet)
Thou hast made them harmless in all their works. (Houbigant)