The Pulpit Commentary
The first and second verses should be read as one sentence, of which the protasis is in Deu_25:1 and the apodosis in Deu_25:2, thus: If there be a strife between men, and they come to judgment, and they (i.e. the judges) give judgment on them, and justify the righteous, and condemn the wicked, then it shall be, if the wicked deserve to be beaten (literally, be the son of blows), that the judge, etc. It is assumed that the judges shall pronounce just judgment, and apportion to the guilty party his due punishment; and then it is prescribed how that is to be inflicted. In the presence of the judge the man was to be cast down, and the adjudged number of blows were to be given him, not, however, exceeding forty, lest the man should be rendered contemptible in the eyes of the people, as if he were a mere slave or brute. This punishment was usually inflicted with a stick (Exo_21:10; 2Sa_7:14, etc.), as is still the case among the Arabs and Egyptians; sometimes also with thorns (Jdg_8:7, Jdg_8:16); sometimes with whips and scorpions, i.e. scourges of cord or leather armed with sharp points or hard knots (1Ki_12:11, 1Ki_12:14). Though the culprit was laid on the ground, it does not appear that the bastinado was used among the Jews as it is now among the Arabs; the back and shoulders were the parts of the body on which the blows fell (Pro_10:13; Pro_19:29; Pro_26:3; Isa_1:6). According to his fault, by a certain number; literally, according to the requirement of his crime in number; i.e. according as his crime deserved. The number was fixed at forty, probably because of the symbolical significance of that number as a measure of completeness. The rabbins fixed the number at thirty-nine, apparently in order that the danger of exceeding the number prescribed by the Law should be diminished (cf. 2Co_11:24); but another reason is assigned by Maimonides, viz. that, as the instrument of punishment was a scourge with three tails, each stroke counted for three, and thus they could not give forty, but only thirty-nine, unless they exceeded the forty (Maimon; 'In Sanhedrin,' 17.2).

The leaving the ox unmuzzled when treading out the corn was in order that the animal might be free to eat of the grains which its labor severed from the husks. This prohibition, therefore, was dictated by a regard to the rights and claims of animals employed in labor; but there is involved in it the general principle that all labor is to be duly requited, and hence it seems to have passed into a proverb, and was applied to men as well as the lower animals (cf. 1Co_9:9; 1Ti_5:18). The use of oxen to tread out the corn and the rule of leaving the animals so employed unmuzzled still prevail among the Arabs and other Eastern peoples.

The Pulpit Commentary
Levirate marriages. If a man who was married died without issue, his surviving brother was required to marry the widow, so as to raise up a successor to the deceased, who should be his heir. The brother who refused this duty must be publicly disgraced. The design of this institution—which was not originated by Moses, but came down from early times (Gen_38:8), and is to be found amongst ether nations than the Jews, and that even in the present day—was to preserve a family from becoming extinct and to secure the property of a family from passing into the hands of a stranger. The notion that the usage "had its natural roots in the desire inherent in man who is born for immortality, and connected with the hitherto undeveloped belief in an eternal life, to secure a continued personal existence for himself and immortality for his name through the perpetuation of his family, and in the life of the son who took his place" (Keil), seems wholly fanciful.

Dwell together; i.e. not necessarily in the same house, but in the same community or place (cf. Gen_13:6; Gen_26:7). And have no child; literally, have no son; but this is rightly interpreted as meaning child (so the LXX.; Vulgate; Josephus, 'Antiq.,' 4.8, 23; Mat_22:25; Maimon; 'In Jibbum.,' 2.6-9); for, if the deceased left a daughter, the perpetuation of the family and the retention of the property might be secured through her (cf. Num_27:4, etc.).

The Pulpit Commentary
Shall succeed in the name of his brother which is dead; literally, shall rise up on the name of his deceased brother; i.e. shall be enrolled in the family register as heir of the deceased, and shall perpetuate his name.

The Pulpit Commentary
If the man refused to marry the widow of his deceased brother, he was free to do so; but the woman had her redress. She was to bring the matter before the eiders of the town, sitting as magistrates at the gate, and they were to summon the man and speak to him, and if he persisted in his refusal, the woman was to take his shoe from off his foot, and spit before his face, and say, So shall it be done unto that man that will not build up his brother's house. The taking off of the shoe of the man by the woman was an act of indignity to him; it amounted to a declaration that he was not worthy to stand in his brother's place, and was scornfully rejected by the woman herself. As the planting of the shod foot on a piece of property, or the casting of the shoe over a field, was emblematical of taking possession of it with satisfaction (Psa_60:8; Psa_108:9); and as the voluntary handing of one's shoe to another betokened the giving up to that other of some property or right; so, contrariwise, the forcible removal from one of his shoe and the casting of it aside indicated contemptuous rejection of the owner, and repudiation of all his rights and claims in the matter. To walk barefooted was regarded by the Jews as ignominious and miserable (cf. Isa_20:2, Isa_20:4; 2Sa_15:30). The spitting before the face of the man (בְּפָנַיו in front of him) is by the Jewish interpreters understood of spitting on the ground in his presence. This seems to be what the words express (cf. Deu_4:37; Deu_7:24; Deu_11:25; Jos_10:8; Eze_10:8, for the rendering of בפני); and this, according to Oriental notions, would be insult enough (cf. Num_12:14; Isa_1:6; Niebuhr, ' Description de l'Arabie,' 1.49).

Deu_25:11, Deu_25:12

But though the childless widow might thus approach and lay hold on the man, no license was thus granted to women to pass beyond the bounds of decency in their approaches to the other sex. Hence the prohibition in these verses. The severe sentence here prescribed was by the rabbins commuted into a fine of the value of the hand.

Rectitude and integrity in trade are here anew inculcated (cf. Le 19:35, etc.).

Diverse weights; literally, a stone and a stone—a large one for buying, and a small one for selling (cf. Amo_8:5). Both weights and measures were to be "perfect," i.e. exactly correct, and so just. (On the promise in Deu_25:15, see Deu_4:26; Deu_5:16.)

The Pulpit Commentary
(Cf. Deu_22:5; Deu_23:12.) All that do unrighteously; equivalent to all that transgress any law.

The Pulpit Commentary
Whilst in their intercourse with each other the law of love and brotherly kindness was to predominate, it was to be otherwise in regard to the enemies of God and his people. Them they were to overcome by force; wickedness was to be removed by the extinction of the wicked. Moses has already repeatedly reminded the Israelites that they had utterly to destroy the wicked nations of Canaan; and he here closes this discourse by reminding them that there was a nation outside of Canaan which was also doomed, and which they were to root out. This was Amalek, which had attacked the Israelites in their journey at Rephidim, and had taken advantage of their exhausted condition to harass their rear and destroy those who, faint and weary, had lagged behind. For this they had been already punished by the Israelites, who, led on by Joshua, had turned upon them and discomfited them with the edge of the sword. This, however, was not enough; Amalek was to be utterly destroyed, and this the Israelites were to effect as soon as the Lord had given them rest in the Promised Land. It was not, however, till the time of David that this was done.

And smote the hindmost of thee; literally, and tailed thee; i.e. cut off thy tail, or rear. The verb (זִנֵּב) occurs only here and in Jos_10:19. It is a denominative from זָנָב, a tail, and, like many denominatives, both in the Hebrew and in other languages, it has the sense of taking away or cutting off the thing expressed by the noun from which it is formed, like the English verb to skin, for example.