What sins are just bein adam l'chaveiro?

Question

The mishan in Mas. Yom Kippur (8:9) says that Yom Kippur is not mechapeir sins that are bein adam l'chaveiro, between a man and his friend. Therefore, it seems that our prayers for forgiveness on that day should be centered on sins between ourselves and hamakom because for those, the day is efficacious. But in the litany of sins (the al cheit) we confess and ask forgiveness for, the following sins (or sin categories) are included:

hona'at re'a

zilzul horim umorim

chozek yad

chapat shochad

lashon hara

masa u'vmatan

neshech u'vmarbit

tzdiyat re'a

r'chiliut

I can understand how one could extend any of these to include an aspect of bein adam l'makom, or how some could be offensive to hashem even though they don't somehow, rise to the level of actionable when involving another person in a certain way, but some these, especially ones about extortion or bribing seem pretty clearly about our interactions with others. If so, why are they included if Yom Kippur is not designed to be mechapeir them?

Or are there other sins which are not on this list that are purely between people so they aren't covered but somehow, the ones on this list are. Any clarification would be appreciated.

Answer 1

Rabbeinu Yona in chapter 4 explains that after getting the mechila you still need vidduy, but that vidduy prior to getting forgiveness doesn’t work

ואמרו רבותינו זכרונם לברכה מכל חטאתיכם לפני ה' תטהרו עבירות שבין אדם למקום יום הכפורים מכפר. עברות שבין אדם לחברו אין יום הכפורים מכפר עד שירצה את חברו. לכן מי שגזל את חברו. ישיב את הגזלה ואחרי כן יתודה. ואם התודה תחילה. לא עלה לו הודוי. כמו שאמרו רבותינו זכרונם לברכה בענין הגוזל והנשבע לשקר. שהוא חייב לשלם קרן וחומש ולהביא אשם. שהמביא גזלו עד שלא הביא אשמו - יצא. אשמו עד שלא הביא גזלו - לא יצא. שנאמר בענין גזל הגר שאין לו יורשין ונותן התשלומין לכהן (במדבר ה׳:ח׳) האשם המושב לה' לכהן מלבד איל הכפרים אשר יכפר בו עליו. פירושו - האשם הנזכר במקרא הזה הוא על התשלומין. מלשון (שם) ונתן לאשר אשם לו. והוא מביא התשלומין מלבד איל הכפרים אשר יכפר בו עליו אחרי כן:

And our Rabbis, may their memory be blessed, said (Yoma 85b), “‘Of all your sins; you shall be pure before the Lord’ - Yom Kippur atones for transgressions between a person and the Omnipresent. Yom Kippur does not atone for transgressions between a person and his fellow until he appeases his fellow.” Hence one who has robbed his fellow must return the theft and confess afterwards. But if he confesses first, his confession is ineffective. [This is] as our Rabbis, may their memory be blessed, said (Bava Kamma 110a) concerning a robber or one who swears falsely [about his debt] who is obligated to pay the principal and a fifth, and to bring a guilt-offering - that one who brings his theft before he has brought his guilt-offering has fulfilled [his obligation]; his guilt-offering before he has brought his theft has not fulfilled [his obligation]. For it is stated concerning the robber of a convert that has no heirs, such that [the robber] must give the repayments to a priest, (Numbers 5:8) “then the guilt shall be to the Lord for the priest; besides the ram of atonement with which atonement is made on his behalf.” Its explanation: The guilt that is mentioned in this verse is referring to the repayment - from the usage (Numbers 5:7), “and he shall give it to whom he is guilty.” And he brings the repayment [first], “besides the ram of atonement with which atonement is made on his behalf” afterwards.