1. It was customary among the Jews to hang a copy of their laws in a public place, and some commentators suppose an allusion to this custom to be made here.
2. Jewish teachers have at various times attempted to make compendiums of the law. Tholuck gives a very interesting account of one of the most remarkable of these made by Rabbi Samlai, and contained in the Gemara. The following is a condensed statement of Samlai’s compendium of the law: Moses gave six hundred and thirteen commandments on Mount Sinai. David reduced these commandments to eleven, which may be found in the fifteenth Psalm, in answer to the question, “Lord, who shall abide in thy tabernacle?” Afterward Isaiah came and reduced the eleven to six, as may be seen in Isaiah 33:1616He shall dwell on high: his place of defence shall be the munitions of rocks: bread shall be given him; his waters shall be sure. (Isaiah 33:16). Then came Micah and reduced the six to three. See Micah 6:88He hath showed thee, O man, what is good; and what doth the Lord require of thee, but to do justly, and to love mercy, and to walk humbly with thy God? (Micah 6:8). Once more Isaiah brought down the three to two (Isa. 61:11The Spirit of the Lord God is upon me; because the Lord hath anointed me to preach good tidings unto the meek; he hath sent me to bind up the brokenhearted, to proclaim liberty to the captives, and the opening of the prison to them that are bound; (Isaiah 61:1)). Lastly came Habakkuk, and reduced them all to one: “The just shall live by faith” (Hab. 2:44Behold, his soul which is lifted up is not upright in him: but the just shall live by his faith. (Habakkuk 2:4)). See Tholuck's Commentary on the Sermon on the Mount, (Am. Ed.), p. 139.