Rambam: Mechirah - Chapter Fourteen
18. Verbally abusing a person is more severe than taking unfair advantage of him financially. For the latter can be repaid, while the former can never be repaid. The latter involves only the person's possessions, while the former involves his person.
And with regard to verbal abuse, Leviticus 25:17 states: "And you shall fear your God," for the matter is one of feelings. With regard to all matters of feeling, the Torah states: "And you shall fear your God."
Whenever a person cries out because of verbal abuse, he is answered immediately, as implied by the conclusion of the above verse: "...I am God."
