האם יש איסור נקמה בלב - ללא דיבור

(18) You shall not take vengeance or bear a grudge against members of your people. Love your fellow [Israelite] as yourself: I am יהוה.

1) לא תקם THOU SHALT NOT AVENGE — If one says to another “Lend me your sickle", and he replies, “No!", and the next day he (the latter) says to him (the former), “Lend me your hatchet”, and he retorts, “I am not going to lend it to you, just as you refused to lend me your sickle״ — this is avenging. And what is “bearing a grudge”? If one says to another, “Lend me your hatchet”, and he replies “No!” and on the next day he says to him “Lend me your sickle”, and he replies: “Here it is; I am not like you, because you would not lend me” — this is called “bearing a grudge (נטירה)” because he retains (נוטר) enmity in his heart although he does not actually avenge himself (Sifra, Kedoshim, Chapter 4 10-11; Yoma 23a).

(38) “You shall not take vengeance or bear a grudge against your countrymen.” (Leviticus 19:18). Our Rabbis, may their memory be blessed, said (Yoma 23a), “What is revenge [... If] one said to [his fellow,] ‘Lend me your ax’; he said [back] to him, ‘I will not lend to you, just as you did not lend yours to me’ - that is revenge. And what is bearing a grudge? [...] he said [back] to him, ‘Here it is, as I am not like you, who would not lend it to me.’” And the punishment for this is not for speaking, but rather for the grudge in the heart. And our Rabbis, may their memory be blessed, said (Yoma 23a) the [prohibition] on bearing a grudge is for monetary matters, but it is permissible to keep words of pride or disgrace or seeking evil [against him] upon his heart. And our Rabbis, may their memory be blessed, said (Yoma 22b), “Any Torah scholar who [when insulted] does not avenge himself and bear a grudge like a snake is not considered a Torah scholar.” But if they request forgiveness from him, he should forego his reckonings.

HATRED AND VENGEANCE: Hatred and vengeance are likewise exceedingly difficult for the mocked heart of human beings to escape from. For a human being strongly feels insults and he experiences great pain therein. Revenge is then sweeter to him than honey for it alone is his peace. Therefore for one to have the strength to relinquish what his nature impels him to and to overlook the wronging, not hating the one who ignited hatred in his heart, not exacting vengeance when he has the opportunity to do so nor bearing a grudge against him, but rather to forget the whole incident and remove it from his heart as if it had never happened - he is mighty and courageous. Such forbearance is easy only to the ministering angels who do not have among them these traits, but not to human beings "who dwell in houses of clay, whose foundation is in the dust" (Job 4:19). But it is a decree of the King, and the scriptural verses state in explicit and clear language, requiring no explanation: "you shall not hate your brother in your heart" (Vayikra 19:17), "you shall not take vengeance nor bear a grudge against the members of your people" (Vayikra 19:18). The explanation of taking vengeance and bearing a grudge is known.