(25) If thou wilt make me an altar of stone.--Among civilised nations altars were almost always of stone, which superseded earth, as more durable. God does not absolutely prohibit the employment of stone altars by the Israelites, who are found to use them upon certain occasions (Joshua 8:31; 1Kings 18:32). He is content to forbid the shaping of the stones by an implement, that so they may not give rise to idolatry. (See Note on Exodus 20:24.)

Thou hast polluted it.--Nature is God's handiwork, and, therefore, pure and holy. Man, by contact with it, imparts to it of his impurity. The altar, whereby sin was to be expiated, required to be free from all taint of human corruption. For the construction of the altar afterwards sanctioned, see the comment on Exodus 27:1.

Verse 25. - And if thou wilt make me an altar of stone - i.e., if, notwithstanding my preference expressed for an altar of earth, thou wilt insist on making me one of stone, as more permanent, and so more honourable, then I require that the stones shall be rough stones shaped by nature, not stones chiselled into shape by the art of man. For if thou lift up thy tool upon it thou hast polluted it. It is conjectured with reason that we have here an old traditional idea, which God thought fit under the existing circumstances to sanction. The real object was that altars should not be elaborately carved with objects that might superinduce idolatry. The widely prevalent notion, that nature is sacred, and that all man's interference with nature is a defilement, was made use of economically, to produce the desired result. No tool being allowed to be used, no forms of living creatures could be engraved, and so no idolatry of them could grow up.

20:22-26 Moses having entered into the thick darkness, God there spake in his hearing all that follows from hence to the end of chap. 23, which is mostly an exposition of the ten commandments. The laws in these verses relate to God's worship. The Israelites are assured of God's gracious acceptance of their devotions. Under the gospel, men are encouraged to pray every where, and wherever God's people meet in his name to worship him, he will be in the midst of them; there he will come unto them, and will bless them.And if thou wilt make me an altar of stone,.... If they chose instead of an earthen one to make one of stone, as they might in rocky places, where they came, and in such an one where they now were, Mount Sinai, under which hill an altar was built, Exodus 24:4,

thou shall not build it of hewn stone; which would require time and occasion expense, to hew and polish them in an artificial way; but it was to be built of rude and unpolished stones, just as they were taken out of the quarry, or found lying by the way, and which were laid up in an heap one upon another, and was done with little trouble, and without any ornament, and easily separated and thrown down, when become useless: the reason of this law, as given by Maimonides (w), is this,"because the idolaters of that time built their altars of hewn stones, therefore God forbad it, lest we should be like them, and that we might shun it in all things, he commanded the altar to be made of earth, as it is said, an altar of earth shalt thou make unto me; and if it could not be made without stones, that the stones should remain in their own natural form, and be neither hewn nor polished; as he after forbad a painted stone, and a plantation of trees by an altar; for in each of these there is one and the same intention and design, namely, that we might not worship him in the same manner in which idolaters used to worship their fictitious deities:"

for if thou lift up thy tool upon it; or, thy sword (x); it signifies any tool or instrument made of iron as a sword is, and here such an one as is used in hewing of stone; which, if lifted up on the altar, or on any of the stones of which it is built, to strike and hew them with:

thou hast polluted it; and so made it unfit for use: how this should be done hereby is not easy to say, no good reason seems to be assignable for it but the will and pleasure of God; who so appointed it, and reckoned that a pollution, and would have it so thought by others, which with men is accounted ornamental; his thoughts and judgment are not as man's: the Targum of Jonathan is,"for if thou liftest up iron, of which a sword is made, upon a stone, thou wilt profane it;''the reason which the Misnic doctors (y) give, and Jarchi from them, is,"because iron was created to shorten the days of men, but the other was made to prolong the days of men: and therefore it cannot be just that that which shortens should be lifted up and agitated over that which prolongs:''but Maimonides gives a better reason of it, as Abarbinel understands him, which was to prevent persons making images in stones (z), which image making is the thing guarded against and forbidden in the context; but still better is that of Isaac Arama (a), that the hands of the artificer were to abstain from the stones of the altar, lest that good which men obtain of God at the altar should be attributed to any work of theirs: though, after all, it is right what Aben Ezra, says, that it does not belong to us to search after the reasons of the commands, at least not in too curious and bold a manner, and where God is silent and has not thought fit to give any.

(w) Moreh Nevochim, par. 3. c. 45. (x) "gladium tuum", Montanus, Piscator, Cartwright. (y) Misnah Middot, c. 3. sect. 4. (z) Apud L'Empereur in Middot, ib. (a) Apud Rivet in loc.