What is Tithing?
The word "tithe" literally means "to give a tenth part," such as regarding produce or land, although in modern vernacular it often refer to one's financial offering given for religious reasons, like in the Christian religion.
The custom of giving a 10th part of the products of the land and of the spoils of war to priests and kings (1 Macc 10:31; 11:35; 1 Sam 8:15,17) was a very ancient one among most nations. That the Jews had this custom long before the institution of the Mosaic Law is shown by Gen 14:17-20 (compare Heb 7:4) and Gen 28:22.
Many critics hold that these two passages are late and only reflect the later practice of the nation; but the payment of tithes is so ancient and deeply rooted in the history of the human race that it seems much simpler and more natural to believe that among the Jews the practice was in existence long before the time of Moses.
Tithing in the Pentateuch
In the Pentateuch we find legislation as to tithes in three places. (1) According to Lev 27:30-33, a tithe had to be given of the seed of the land, i.e. of the crops, of the fruit of the tree, e.g. oil and wine, and of the herd or the flock (compare Dt 14:22,23; 2 Ch 31:5,6). As the herds and flocks passed out to pasture they were counted (compare Jer 33:13; Ezek 20:37), and every 10th animal that came out was reckoned holy to the Lord.
The owner was not allowed to search among them to find whether they were bad or good, nor could he change any of them; if he did, both the one chosen and the one for which it was changed were holy. Tithes of the herds and flocks could not be redeemed for money, but tithes of the seed of the land and of fruit could be, but a 5th part of the value of the tithe had to be added. (2) In Nu 18:21-32 it is laid down that the tithe must be paid to the Levites. (It should be noted that according to Heb 7:5, `they that are of the sons of Levi, who receive the office of the priesthood .... take tithes of the people.'
Westcott's explanation is that the priests, who received from the Levites a tithe of the tithe, thus symbolically received the whole tithe. In the time of the second temple the priests did actually receive the tithes. In the Talmud (Yebhamoth 86a et passim) it is said that this alteration from the Mosaic Law was caused by the sin of the Levites, who were not eager to return to Jerusalem, but had to be persuaded to do so by Ezra (Ezr 8:15).) The Levites were to receive the tithes offered by Israel to Yahweh, because they had no other inheritance, and in return for their service of the tabernacle (Nu 18:21,24).
The tithe was to consist of corn of the threshing-floor and the fullness of the wine press (Nu 18:27), which coincides with seed of the land and fruit of the trees in Lev 27. The Levites, who stood in the same relation to the priests as the people did to themselves, were to offer from this their inheritance a heave offering, a tithe of a tithe, to the priests (compare Neh 10:39), and for this tithey were to choose of the best part of what they received. (3) In Dt 12:5,6,11,18 (compare Am 4:4) it is said that the tithe is to be brought "unto the place which Yahweh your God shall choose out of all your tribes, to put his name there," i.e. to Jerusalem; and in Dt 12:7,12,18, that the tithe should be used there as a sacred meal by the offerer and his household, including the Levite within his gates.
Nothing is said here about tithing cattle, only grain, wine and oil being mentioned (compare Neh 10:36-38; 13:5,12). In Dt 14:22-29 it is laid down that if the way was too long to carry the tithe to Jerusalem it could be exchanged for money, and the money taken there instead, where it was to be spent in anything the owner chose; and whatever was bought was to be eaten by him and his household and the Levites at Jerusalem.
In the third year the tithe was to be reserved and eaten at home by the Levite, the stranger, the fatherless and the widow. In Dt 26:12-15 it is laid down that in the 3rd year, after this feast had been given, the landowner should go up himself before the Lord his God, i.e. to Jerusalem, and ask God's blessing on his deed. (According to the Mishna, CoTah 9 10; Ma`aser Sheni 5 65, the high priest Johanan abolished this custom.) In this passage this 3rd year is called "the year of tithing."
There is thus an obvious apparent discrepancy between the legislation in Leviticus and Deuteronomy. It is harmonized in Jewish tradition, not only theoretically but in practice, by considering the tithes as three different tithes, which are named the First Tithe, the Second Tithe, and the Poor Tithe, which is called also the Third Tithe (Pe'ah, Ma`aseroth, Ma`ser Sheni, Dema'i, Ro'sh ha-shanah; compare Tobit 1:7,8; Ant, IV, iv, 3; viii, 8; viii, 22).
According to this explanation, after the tithe (the First Tithe) was given to the Levites (of which they had to give the tithe to the priests), a Second Tithe of the remaining nine-tenths had to be set apart and consumed in Jerusalem. Those who lived far from Jerusalem could change this Second Tithe into money with the addition of a 5th part of its value. Only food, drink or ointment could be bought for the money (Ma`aser Sheni 2 1; compare Dt 14:26).
The tithe of cattle belonged to the Second Tithe, and was to be used for the feast in Jerusalem (Zebhachim 5 8). In the 3rd year the Second Tithe was to be given entirely to the Levites and the poor. But according to Josephus (Ant., IV, viii, 22) the "Poor Tithe" was actually a third one. The priests and the Levites, if landowners, were also obliged to give the Poor Tithe (Pe'ah 1 6).
The explanation given by many critics, that the discrepancy between Deuteronomy and Leviticus is due to the fact that these are different layers of legislation, and that the Levitical tithe is a post-exilian creation of the Priestly Code, is not wholly satisfactory, for the following reasons: (1) The allusion in Dt 18:1,2 seems to refer to the Levitical tithe. (2) There is no relation between the law of Nu 18 and post-exilian conditions, when the priests were numerous and the Levites a handful. (3) A community so poor and disaffected as that of Ezra's time would have refused to submit to a new and oppressive tithe burden. (4) The division into priests and Levites cannot have been of the recent origin that is alleged.
W. R. Smith and others suggest that the tithe is simply a later form of the first-fruits, but this is difficult to accept, since the first-fruits were given to the priest, while the tithes were not. The whole subject is involved in considerable obscurity, which with our present information cannot easily be cleared away.
The Talmudic law of tithing extends the Mosaic Law, with most burdensome minuteness, even to the smallest products of the soil. Of these, according to some, not only the seeds, but, in certain cases, even the leaves and stalks had to be tithed (Ma`aseroth 4 5), "mint, anise, and cummin" (Dema'i 11 1; compare Mt 23:23; Lk 11:42). The general principle was that "everything that is eaten, that is watched over, and that grows out of the earth" must be tithed (Ma`aseroth 1 1).
Considering the many taxes, religious and secular, that the Jews had to pay, especially in post-exilian times, we cannot but admire the liberality and resourcefulness of the Jewish people. Only in the years just after the return from exile do we hear that the taxes were only partially paid (Neh 13:10; compare Mal 1:7 ff; and for pre-exilian times compare 2 Ch 31:4 ff). In later times such cases seldom occur (Sotah 48a), which is the more surprising since the priests, who benefited so much by these laws of the scribes, were the adversaries of the latter.Source
Schaff-Herzog Encyclopedia of Religious Knowledge" (in the public domain), "Tithing" with minor edits.