Verse 2. - On the day when ye shall pass over Jordan; i.e. at the time; "day" is here used in a wide sense (cf. Genesis 2:4; Numbers 3:1; 2 Samuel 22:1; Ecclesiastes 12:3; Isaiah 11:10, etc.). Thou shalt set thee up great stones, and plaster them with plaster, The stones, the number of which is not specified, were to be large, because much was to be inscribed upon them, and they were to be covered with a coating of lime or gypsum (שִׂיַד), in order to secure a smooth white surface on which the inscription might be clearly depicted. That the words were not, as Michaelis, Rosenmüller, and others suppose, cut in the stone, and afterwards covered with plaster in order to preserve them, is plain from its being enjoined that they were to be written upon (עַל) the stones so prepared; and besides, as this was intended to be a proclamation of the Law, the main purpose of the erection would have been frustrated had the inscription been concealed by such a covering as that supposed. Among the ancient Egyptians the practice of depicting records on walls or monuments covered with a coating of plaster was common (see Hengstenberg, 'Authentic des Pent.,' 1:464, English translation, 1:433); from them, doubtless, it was borrowed by the Hebrews. It has been suggested by Kennicott that the writing was to be in relieve, and that the spaces between the letters were filled up by the mortar or cement. This is possible, but it is not such a process as this that the words of the text suggest. "A careful examination of Deuteronomy 27:4, 8, and Joshua 8:30-22, will lead to the opinion that the Law was written upon or in the plaster with which these pillars were coated. This could easily be done, and such writing was common in ancient times. I have seen specimens of it certainly more than two thousand years old, and still as distinct as when they were first inscribed on the plaster" (Thomson, 'Land and the Book,' it. p. 204).

27:1-10 As soon as they were come into Canaan, they must set up a monument, on which they must write the words of this law. They must set up an altar. The word and prayer must go together. Though they might not, of their own heads, set up any altar besides that at the tabernacle; yet, by the appointment of God, they might, upon special occasion. This altar must be made of unhewn stones, such as they found upon the field. Christ, our Altar, is a stone cut out of the mountain without hands, refused by the builders, as having no form or comeliness, but accepted of God the Father, and made the Head of the corner. In the Old Testament the words of the law are written, with the curse annexed; which would overcome us with horror, if we had not, in the New Testament, an altar erected close by, which gives consolation. Blessed be God, the printed copies of the Scriptures among us, do away the necessity of such methods as were presented to Israel. The end of the gospel ministry is, and the end of preachers ought to be, to make the word of God as plain as possible. Yet, unless the Spirit of God prosper such labours with Divine power, we shall not, even by these means, be made wise unto salvation: for this blessing we should therefore daily and earnestly pray.And it shall be, on the day when you shall pass over Jordan,.... Not the precise day exactly, but about that time, a little after they passed that river, as soon as they conveniently could; for it was not till after Ai was destroyed that the following order was put in execution; indeed as soon as they passed over Jordan, they were ordered to take twelve stones, and did; but then they were set up in a different place, and for a different purpose; see Joshua 4:3,

unto the land which the Lord thy God giveth thee, that thou shalt set thee up great stones; not in Jordan, as Jarchi, but on Mount Ebal, Deuteronomy 27:4; nor had the stones set up in Jordan any such inscription as what is here ordered to be set on these:

and plaster them with plaster: that so words might be written upon them, and be more conspicuous, and more easily read.