LEV58 Our Sages, z"l, said (Yoma 85b), "'[For on this day …] you shall be purified for all your sins before Hashem' (Vayikra 16:30) -- Yom Kippur atones for sins that are between man and God (i.e., "sins before Hashem."); Yom Kippur does not atone for sins that are between one man and another, until he appeases his fellow man." As such, one who robs another must [first] return what he stole and then confess his sins. If he first confesses his sin, the confession is not taken into account, as our Sages z"l, said (Bava Kama 110a) in connection with one who robs and [then] swears falsely (i.e., denying that he had stolen the item.), who then must return the principal, add a fifth [this verse; i.e. a quarter of the value of the principal, which is a fifth of both combined. For example, if he stole $100 ("the principal"), he must add $25, which is one-fifth of the $125 he will repay in total. See Vayikra 5:20-26], and bring a guilt-offering: if he returns what he stole before bringing his guilt-offering, he has fulfilled his obligation (i.e., he has fulfilled his obligation of bringing a guilt-offering--the sacrifice is valid); but if he brings his guilt-offering prior to returning what he stole, he has not fulfilled his obligation (the guilt-offering requires confession (Mishneh Torah, Hilchos Ma'aseh Ha-korbanos 3:14). Thus we see that what was stolen must first be returned before confessing the sin. ... He first must bring restitution, and only afterwards [does it say], "… Besides the ram of atonement for which the [Kohen] shall make atonement for him." (i.e., one who steals from a convert who has no heirs must pay back what he stole to Kohanim; only afterwards can he bring his guilt-offering).