Deuteronomy 17:16

“But he shall not multiply horses to himself, etc.] That he might not put his trust and confidence in outward things, as some are apt to trust in horses and chariots; and that he might not tyrannise over and distress his subjects by keeping a number of horses and chariots as a standing army, and chiefly for a reason that follows; he was to have no more than for his own chariot, so Jarchi, and so the Misnah f195 and Maimonides f196; the Targum of Jonathan restrains it to two: nor cause the people to return to Egypt, to the end that he should multiply horses; which was a country that abounded with them, and therefore he was not to encourage, and much less oblige his subjects to travel thither…”

“he shall not multiply horses to himself--The use of these animals was not absolutely prohibited, nor is there any reason to conclude that they might not be employed as part of the state equipage. But the multiplication of horses would inevitably lead to many evils, to increased intercourse with foreign nations, especially with Egypt, to the importation of an animal to which the character of the country was not suited, to the establishment of an Oriental military despotism, to proud and pompous parade in peace, to a dependence upon Egypt in time of war, and a consequent withdrawal of trust and confidence in God. (Sa2 8:4; Kg1 10:26; Ch2 1:16; Ch2 9:28; Isa 31:3).”

“The horse was not anciently used in the East for purposes of agriculture or traveling, but ordinarily for war only. He appears constantly in Scripture as the symbol and embodiment of fleshly strength and the might of the creature (compare Psalms 20:7; Psalms 33:16-17; Psalms 147:10; Job 39:19 ff), and is sometimes significantly spoken of simply as “the strong one” (compare Jeremiah 8:16). The spirit of the prohibition therefore is that the king of Israel must not, like other earthly potentates, put his trust in costly and formidable preparations for war (compare Hosea 1:7). Egypt was the principal source from where the nations of western Asia drew their supplies of this animal (compare…”

“He shall not multiply horses - Tho' he might have horses for his own use, yet he was not to have many horses for his officers and guard, much less for war, lest he should trust in them. The multiplying horses is also forbidden, lest it should raise too great a correspondence with Egypt which furnished Canaan with them. The Lord hath said - The Lord hath now said to me, and I by his command declare it to you. Ye shall no more return that way - Into Egypt, lest ye be again infected with her idolatries. Deuteronomy 17:17”

“17:16 never return to Egypt: Going there would show a king’s lack of dependence on God, who had redeemed Israel from bondage to Egypt. The best horses were found in Egypt (see 1 Kgs 10:28-29).”

“multiply horses: Multiplying horses for chariots of war and cavalry, or for luxury, would increase the splendour of a monarch, and form a ground of confidence distinct from a proper confidence in God, and inconsistent with it, and with considering him as the glory of Israel. Egypt abounded in horses; and the desire of multiplying these would induce the prince to encourage a trade with that kingdom; and this might make way for the Israelites being again subjugated by the Egyptians, or at least corrupted by their idolatries and vices. Whereas, it was the command of God that they should no more return thither, but be totally detached from them. Besides, they might be tempted to extend their…”