Matthew 23:5

phylacteries Greek φυλακτήρια = "defences," and in late Greek "amulets" or "charms." The Hebrew name, tephillin, which is still in use, signifies "prayers." They were slips of parchment inscribed with four portions of the Law (Exodus 12:3-16; Deuteronomy 6:5-9; Deuteronomy 11:13-21) enclosed in little cases or boxes made of calf-skin, and fastened by leather straps to the left arm and on the forehead, in accordance with a literal interpretation of Exodus 13:16 and Deuteronomy 6:8. To make the phylacteries, or rather the cases which contained them, broad and conspicuous was to assume a character of superior piety, for the phylacteries were symbols of devotion.

Jesus does not prohibit the practice of wearing phylacteries, but the ostentatious enlargement of them. It is thought by many that our Saviour Himself wore phylacteries.

enlarge the borders of their garments Strictly, the fringe of the talith, or cloak: another instance of ostentation; the blue threads in the fringe, the colour of the sky were a type of heavenly purity. Our Lord Himself wore the fringed talith (see ch. Matthew 9:20); the offence of the Pharisees consisted in enlarging the symbolical fringes.