Or HaChaim on Numbers 5:9/אור החיים על במדבר ה׳:ט׳

1 וכל תרומה…לו יהיה, "and every heave-offering…..shall be his." Why did the Torah repeat the same subject three times (verses 9 and 10)? Furthermore, why did the Torah repeat the same words, i.e. לו יהיה? Our sages in the Sifri explain that the apparently superfluous words "they shall be his" refer to the offering of the first ripe fruit which are normally called ראשית. They too are to be treated in the same way as the heave-offerings, תרומה. They become the priest's personal property. The second time the Torah repeats this expression it refers to priests who performed Temple service at a time which had not been allocated to them. If such a priest offered his own offering i.e. קדשיו, it remained his although his presence in the Temple at the time had not been authorised. The words אשר יתן לכהן לו יהיה refer to a situation when a father had given to the priest money to redeem his firstborn son and that baby had died after 30 days. The Torah legislates that the priest does not need to return this redemption money to the father. There are numerous other halachic Midrashim in this vein. All of this does not suffice to explain the plain meaning of these verses.

2I believe that we may approach these verses in accordance with the principle that when the Torah repeats something three times it is intended to show that we may not use the information contained in those statements exegetically by applying them to other commandments. The three statements teach us rules applying to the 24 types of gifts the Torah has allocated to the priests. In the first chapter of his treatise on the laws of בכורים, first ripe fruits, Maimonides writes that the 24 gifts G'd allocated to the priests were divided into five categories, which in reality are only three basic categories. 1) the portions of the sacrifices which they receive from animals which have been offered on the altar. These included: the meat of the sin-offering; the meat of the guilt-offering; the meat of the peace-offerings paid for by the public purse; the remainder of the Omer, i.e. the barley offering on the second day of the Passover festival; most of the meal-offerings except the fistful offered on the altar; the showbreads; the two loaves offered on Shavuot from the new wheat harvest; the oil of the person undergoing purification rites after having been afflicted with Tzoraat; the skins of any animal offered on the altar; the breast and right flank of all private peace-offerings; left-overs of the thanksgiving offerings; the part of the ram of the Nazirite not presented on the altar; the firstborn male of the pure animals. The first ripe fruit (of the seven species Israel is blessed with). These are 14 gifts allocated to the priests. The common denominateor of all the above is that the owner is obligated to offer them on the altar or bring them to the priest. They are all inherently sacred. The second category are such things as the Terumah, a tithe from the grain-harvest, olive trees or vineyard's produce; the Terumat Maasser i.e. the portion of his tithes the Levite has to give to the priest; Challah, i.e. 1/48th of a dough of certain proportions which the Israelite has to give to the priest. The third category are the gifts such as the tithe of the animals when they are shorn (1 tenth); certain fields which were sold by an Israelite and not redeemed within a specified time; the redemption money paid by a father for retaining his firstborn son; redemption money for the firstborn donkey; properties set aside for use by the priest. Property of an intestate convert stolen from him which is inherited by the priests by decree of the Torah. All the latter are not inherently sacred. They are not handed to the priest but he has to claim them by himself.

3Let us now approach our verses. Concerning the first 14 items mentioned by Maimonides all of which are sacred by definition and which the Israelite is obligated to hand to the priests, the Torah wrote וכל תרומה לכל קדשי בני ישראל. The Torah gives notice that these gifts are sacred by definition. It goes on: אשר יקריבו which they offer as a sacrifice; the Torah mentions that all these items have to be brought to a site which has been sanctified. Concerning the second category the Torah writes that איש את קדשיו לו יהיו. In this instance the Torah does refer to the sacred nature of the gifts but makes no mention of their qualifying as an offering on the altar, seeing the priest himself has to go after these gifts in order to secure his share. Concerning the final seven items the Torah writes איש אשר יתן לכהן, "that which a person has to give to the priest." Nothing is mentioned about any of these things being sacred as they are of an ordinary secular status, i.e. חולין. The word יתן, "he will give, or he may give" alerts us to the fact that a priest may not claim such gifts from the person whose duty it is to dispense them to a priest of his choosing. Once he has become the recipient of the gift, however, it is not reversible, i.e. לו יהיה, it remains his. Please read what I have written in my book Pri Toar item 61 concerning gifts to the priests. The word לו יהיה implies that a priest is cannot refuse to accept such gifts when they are offered to him (compare Yore Deyah 306,4). Having explained all this we see that the Torah had adequate reason to divide the priestly gifts into three categories so that it had to use the word לו יהיה separately for each category. Had the Torah not done so, I would not have known that the priest is obligated to accept these gifts.