in which he teaches that hatred of kinsfolk that may have been forgotten must be forgiven
People must be attentive, if they bear any hatred towards a person who may have said something to anger them or injured them physically in any way. One should beg for forgiveness, and insist three times, and if the person does not agree to reconciliation, even more may be necessary. It is because there are those who have transgressed the commandment "You shall not hate your kinsfolk in your heart" and have forgotten, that during the moment the Torah scrolls are taken out from the ark on Yom Kippur Eve the entire congregation recites, "We have completely forgiven".
Binyamin HaTza'ir, p. 134, Tel Aviv, 1978