Likutei Moharan 74:16/ליקוטי מוהר"ן ע״ד:ט״ז

116. And then tzedek becomes tzedakah, as in “a benevolent sun with healing.” When Malkhut corresponds to judgment, it is called tzedek. Once mitigated by the aspect of Yaakov, it then becomes the aspect of tzedakah, “a benevolent sun,” which corresponds to speech-with-wisdom, as in “It is I,” God, “Who speaks with benevolence, and [Who is] abundantly able to save” (Isaiah 63:1). The soul that previously had been in the aspect of judgment is the aspect of tzedek, constricted consciousness, speech-without-wisdom. Its ascent from tzedek to tzedakah is its mitigation and salvation, as in “speaks with benevolence, and [is] abundantly able to save.”