Deuteronomy 6:8 - Coke's Commentary on the Holy Bible

Ver. 8. Thou shalt bind then, for a sign— The Lord is pleased to take every method most likely to preserve in the minds of the Israelites a conscientious regard to the precepts which he enjoined. He not only commands, that their children be early and diligently instructed in them, but that they should bind them for a sign upon their hands, &c. that is, that they should make them as familiar to them as if they were written upon their arms or foreheads, or upon the posts of their houses, or their gates, ver. 9. Possibly, some part of the command was designed to be understood literally; for it might have been of use to them, when they went in and out of their houses, to read such solemn words as those in the 4th and 5th verses. The Jews, however, have taken the whole literally; for hence they derived their superstitious practice of making their phylacteries, i.e. parchment inscribed with sections of the law, which they bound to the forehead and wrist. We call the practice superstitious, not only because they fancied some peculiar virtue, like a spell, in these phylacteries, or preservatives; but because it is evident to any unprejudiced person, that neither here, nor Exodus 13:9 does Moses speak of tying parchments about their wrists, but of riveting the thing in their hearts; for it appears from Isaiah 49:16 to be a proverbial expression, importing that they should still retain a lively and grateful sense of the divine goodness, and render it as well known and familiar to every succeeding generation, as if they were a perpetual token upon their arms to put them in mind of it. There are similar phrases in all languages; thus Cicero says: Sit inscriptum in fronte uniuscujusque quid de republica sentiat; "Let every citizen have his sentiments of the commonwealth written upon his forehead." Orat. in Catil. I. Calmet, however, not without reason, infers from this passage, that it was customary for people, even in those times, to wear fillets, or the like ornaments, hanging down upon their foreheads. Those in future times, who were desirous to appear more than ordinarily religious, made, with an ostentatious hypocrisy, their phylacteries peculiarly broad. See Matthew 23:5 and Calmet's Dictionary on the word phylacteries.