הלכות תשובה א,ד; ב,ט-יא; ד,ג

(4) Even though Teshuvah atones for all [sins] and the essence of Yom Kippur brings atonement, [there are different levels of sin and hence, differences in the degree of atonement.] There are sins that can be atoned for immediately and other sins which can only be atoned for over the course of time. What is implied?
If a person violates a positive command which is not punishable by karet and repents, he will not leave that place before he is forgiven. Concerning these sins, [Jeremiah 3:22] states: "Return, faithless children! I will heal your rebellious acts."
If a person violates a prohibition that is not punishable by karet or execution by the court and repents, Teshuvah has a tentative effect and Yom Kippur brings atonement as [Leviticus, loc. cit. states "This day will atone for you."
If a person violates [sins punishable by] karet or execution by the court and repents, Teshuvah and Yom Kippur have a tentative effect and the sufferings which come upon him complete the atonement. He will never achieve complete atonement until he endures suffering for concerning these [sins, Psalms 89:33] states: "I will punish their transgression with a rod."***
When does the above apply: When the desecration of God's name is not involved in the transgression. However, a person who desecrated God's name, even though he repented, Yom Kippur arrived while he continued his repentance, and he experienced suffering, will not be granted complete atonement until he dies. The three: repentance, Yom Kippur, and suffering have a tentative effect and death atones as [Isaiah 22:14] states: "It was revealed in my ears [by] the Lord of Hosts, surely this iniquity will not be atoned for until you die."

(9) Teshuvah and Yom Kippur only atone for sins between man and God; for example, a person who ate a forbidden food or engaged in forbidden sexual relations, and the like. However, sins between man and man; for example, someone who injures a colleague, curses a colleague, steals from him, or the like will never be forgiven until he gives his colleague what he owes him and appeases him.


[It must be emphasized that] even if a person restores the money that he owes [the person he wronged], he must appease him and ask him to forgive him.
Even if a person only upset a colleague by saying [certain] things, he must appease him and approach him [repeatedly] until he forgives him.
If his colleague does not desire to forgive him, he should bring a group of three of his friends and approach him with them and request [forgiveness]. If [the wronged party] is not appeased, he should repeat the process a second and third time. If he [still] does not want [to forgive him], he may let him alone and need not pursue [the matter further]. On the contrary, the person who refuses to grant forgiveness is the one considered as the sinner.
[The above does not apply] if [the wronged party] was one's teacher. [In that instance,] a person should continue seeking his forgiveness, even a thousand times, until he forgives him.

(10) It is forbidden for a person to be cruel and refuse to be appeased. Rather, he should be easily pacified, but hard to anger. When the person who wronged him asks for forgiveness, he should forgive him with a complete heart and a willing spirit. Even if he aggravated and wronged him severely, he should not seek revenge or bear a grudge.
This is the path of the seed of Israel and their upright spirit. In contrast, the insensitive gentiles do not act in this manner. Rather, their wrath is preserved forever. Similarly, because the Gibeonites did not forgive and refused to be appeased, [II Samuel 21:2] describes them, as follows: "The Gibeonites are not among the children of Israel."

(11) If a person wronged a colleague and the latter died before he could ask him for forgiveness, he should take ten people and say the following while they are standing before the colleague's grave: "I sinned against God, the Lord of Israel, and against this person by doing the following to him...."
If he owed him money, he should return it to his heirs. If he is unaware of the identity of his heirs, he should place [the sum] in [the hands of] the court and confess.

(3) Among these [24] are five [transgressions] for which it is impossible for the person who commits them to repent completely. They are sins between man and man, concerning which it is impossible to know the person whom one sinned against in order to return [what is owed him] or ask for his forgiveness. They are:
a) One who curses the many without cursing a specific individual from whom he can request forgiveness;
b) One who takes a share of a thief's [gain], for he does not know to whom the stolen article belongs. The thief steals from many, brings him [his share], and he takes it. Furthermore, he reinforces the thief and causes him to sin;
c) One who finds a lost object and does not announce it [immediately] in order to return it to its owners. Afterwards, when he desires to repent, he will not know to whom to return the article;
d) One who eats an ox belonging to the poor, orphans, or widows. These are unfortunate people, who are not well-known or recognized by the public. They wander from city to city and thus, there is no one who can identify them and know to whom the ox belonged in order that it may be returned to him.
e) One who takes a bribe to pervert judgment. He does not know the extent of the perversion or the power [of its implications] in order to pay the [people whom he wronged], for his judgment had a basis. Furthermore, [by taking a bribe], he reinforces the person [who gave it] and causes him to sin.