Or HaChaim on Leviticus 19:9/אור החיים על ויקרא י״ט:ט׳

1 ובקצרכם את קציר ארצכם, "And when you reap the harvest of your land, etc." The Torah commenced this verse by speaking in the plural, whereas it concluded by addressing an individual i.e. לא תכלה פאת שדך, "you (sing.) must not reap the corner of your field." The Torah may have wanted to dispel the faulty notion that when the amount of gleanings, etc. does not amount to anywhere near enough to provide something meaningful for the poor that the law does not apply. We find an example of such thinking in Kings II 4,43 where Gechazi, Elisha's servant, questioned the use of sharing out twenty loaves amongst over one hundred of Elisha's followers. The Torah therefore addresses each farmer individually to tell him that even though his individual contribution is minimal he must abide by this legislation. The Torah uses the singular for each one of the types of gifts for the poor listed in our verse.

2The Torah may have felt forced to write this positive commandment immediately following mention of the severe כרת penalty for the priest who violates the perimeters of eating sacrificial meat. It wanted to disabuse a person who has become guilty of such a penalty from saying to himself that there is no point in observing any of G'd's commandments because he had already forfeited his share of the hereafter by violating a different commandment. The Torah says: "when you reap the harvest of your fields;" this is a reference to the people (i.e. the nation at large) who had "harvested" i.e. cut themselves off by commission of a sin which made them subject to extinction. G'd directs: "do not destroy the corner of your field to harvest it;" this is a warning to the people or individuals not to become guilty of additional misdemeanours. He advises us that not the whole soul will be destroyed. The only part of the personality (soul) which will be destroyed is the branch to which this particular commandment had been addressed in the first place. Other parts of that soul continue to maintain their affinity with their holy origin. Every Jewish soul has roots in the celestial regions, one root corresponding to each of the commandments in the Torah. The Torah continues: ולקט קצירך לא תלקט, "do not gather the gleanings of your harvest." This is a reminder not even to repeat the specific sin for which one has already once become guilty of the כרת penalty. The rationale for this can best be understood in light of a comment by the Ari Zal. He said that it is in the nature of sanctity to leave behind some mark even if its bulk has been erased. If this is so, it follows that although the sinner has "harvested," i.e. put an end to his spiritual career by his sin, there is still a residue of the former sanctity he has forfeited by his deed. The Torah commanded such a sinner to be careful not to commit an act which would wipe out even that residue by repeating his sin, i.e. לקט. It is G'd's hope and desire that this לקט, residue of former sanctity, should prompt the sinner to become a penitent so that G'd will have cause to extend His mercy to him. After all, we are told in Yuma 86 that although a person may be guilty of a variety of sins which are punishable either by execution in this life or כרת at the hands of G'd, his repentance will atone for such sins. We are all aware of the call of Hoseah to the sinner (Hoseah 14,2) to become a penitent and to express his guilt first of all with his lips. Our sages explain in this connection that "repentance is great indeed as it penetrates up until the throne of G'd's glory." The meaning of these words is that although the חוט, the lifeline which connects every Jewish soul directly to that throne, had already been severed so that only the thinnest of threads remains within the sinner, repentance enables the sinner to re-establish contact with the throne of G'd.