*Minor differences ignored. Grouped by changes, with first version listed as example.
Remember what Amalek did unto thee. We have elsewhere seen how the Amalekites were the first who made a hostile attack upon the people, and endeavored to interrupt their journey; and Moses also related the sentence of God against them, the execution of which he now enjoins upon the people. God then swore that there should be perpetual war against them throughout all ages; and, that His threatening might not be frustrated, He appoints His people to take vengeance upon their great cruelty and impiety. For when the Israelites were inflicting no injury nor loss upon them, it was an act of injustice to make war upon peaceful persons proceeding, without doing any wrong, to another land. But humanity was still more grossly violated by them, inasmuch as they did not spare their own kindred, and thus cast away the feelings of nature. It is plain from Genesis 36:12, that the Amalekites were the descendants of Esau; and hence it follows that they were both sprung from the same ancestor, Isaac. It is true that this command seems but little in accordance with religion, that the people should retaliate an injury done to them. I reply, that they are not stimulated to vindictive feelings in these words, but that they are commanded to punish the sins of Amalek with the same severity as those of the other nations. God appears, indeed, to influence them by private motives when He recounts the cruelty shewn by the Amalekites; but we must judge of the intention of the Legislator with reference to His nature, for we know that no angry or hateful passions can be approved by God; and hence it is easy to conclude that the command was such as the people might obey with well-regulated zeal. The first origin of the crime is specified, viz., because they "feared not God," for this must not be taken in its ordinary meaning, but as expressing that they rebelled against God as it were deliberately. For the promise given to Abraham and Isaac could not be unknown to them; but, since Esau, the founder of their race, had fallen from the right of primogeniture, it came to pass that they attempted to bring God's covenant to nought out of wicked and sacrilegious jealousy; and this is the reason why He unites them with the reprobate nations unto the same destruction. The word znv, zineb, which means to crop the tail, is equivalent to making an attack on the rear, where the baggage and invalids are wont to be placed.
Remember what Amalek did unto thee,.... The Amalekites, how they came out against them, and fought with them at Rephidim, Exodus 17:8,
by the way, when ye were come forth out of Egypt; which was an aggravation of their cruel and inhuman action, that they not only came out against them unprovoked, were the aggressors, and fell upon them as they were travelling on the road, but when they were just come out of Egypt, where they had been in hard bondage, and their spirits broken, and they not used to war; and so took them at all these disadvantages, a people that had not in the least injured them.
Let every persecutor and injurer of God's people take warning from the case of the Amalekites. The longer it is before judgement comes, the more dreadful will it be at last. Amalek may remind us of the foes of our souls. May we be enabled to slay all our lusts, all the corruptions both within and without, all the powers of darkness and of the world, which oppose our way to the blessed Saviour.
Remember what Amalek did--This cold-blooded and dastardly atrocity is not narrated in the previous history (Exodus 17:14). It was an unprovoked outrage on the laws of nature and humanity, as well as a daring defiance of that God who had so signally shown His favor towards Israel (see on 1 Samuel 15; 27. 8; 30).
But whilst the Israelites were to make love the guiding principle of their conduct in their dealings with a neighbour, and even with strangers and foes, this love was not to degenerate into weakness or indifference towards open ungodliness. To impress this truth upon the people, Moses concludes the discourse on the law by reminding them of the crafty enmity manifested towards them by Amalek on their march out of Egypt, and with the command to root out the Amalekites (cf. Exodus 17:9-16). This heathen nation had come against Israel on its journey, viz., at Rephidim in Horeb, and had attacked its rear: "All the enfeebled behind thee, whilst thou wast faint and weary, without fearing God." זנּב, lit., to tail, hence to attack or destroy the rear of an army or of a travelling people (cf. Joshua 10:19). For this reason, when the Lord should have given Israel rest in the land of its inheritance, it was to root out the remembrance of Amalek under heaven. (On the execution of this command, see 1 Sam 15.) "Thou shalt not forget it:" an emphatic enforcement of the "remember" in Deuteronomy 25:17.
Out of Egypt - Which circumstance greatly aggravates their sin, that they should do thus to a people, who had been long exercised with sore afflictions, to whom pity was due by the laws of nature and humanity, and for whose rescue God had in so glorious a manner appeared, which they could not be ignorant of. So this was barbarousness to Israel, and setting the great Jehovah at defiance.
*More commentary available at chapter level.