Likutei Moharan 241:2/ליקוטי מוהר"ן רמ״א:ב׳

12. This is the explanation of “Pinchas, the son of Elazar… turned away My anger… by taking revenge for My sake that I did not destroy [the Jews]” (Numbers 25:11). That is, Pinchas turned away God’s anger and removed the Attribute of Judgment from Israel by assuming the mantle of vengeance to take revenge against them. The judgments therefore ceased, as explained above. The reason for this is that the judgments are unable to destroy [someone totally, and] so they prefer it when a human being wishes to seek revenge, as explained above.

2This is the explanation of “I did not destroy the Jews with My vengeance” (ibid.). That is, with this the Torah informs us of the great favor that Pinchas did for the Jews by taking revenge for the Holy One and assuming the mantle of vengeance to take revenge against them. With this, he did them a great favor. The reason [it was such a great favor] was “so that I did not destroy the Jews with My vengeance.” That is, “with My vengeance,” with My Attribute of Judgment, I did not destroy the Jews because the Attribute of Judgment does not have the ability to destroy, as explained above.

3However, when a human being takes revenge, he is capable of destroying totally, God forbid. Pinchas thus did an amazing favor for the Jews by assuming the mantle of vengeance to take revenge against them. It was this that weakened the force of the judgments against the Jews, by getting [the judgments] to think that Pinchas would take greater revenge, on account of Pinchas being human, with the ability to inflict greater revenge [and even] to destroy totally, God forbid.

4Thus, it was through this that “Pinchas turned away My anger” and removed the Attribute of Judgment, as explained above. However, Pinchas was in fact a most compassionate person, and afterwards certainly eased the judgments from [the Jews]. <That is, Pinchas transposed the word “ChaMaTI (My anger)” into “MaChiTI (I have wiped away) your sins like a cloud” (Isaiah 44:22) .>