Small leather boxes containing miniature Scripture scrolls, bound by Jewish men on the forehead and arm in literal fulfillment of Deut 6:8 (thou shalt bind them for a sign upon thine hand, and they shall be as frontlets between thine eyes; cf. Ex 13:9, 16; Deut 11:18). Hebrew tefillin. The boxes contained passages from the Torah, especially the Shema (Deut 6:4-9), and were worn during morning prayer. The commandment itself is debated as to whether it intends literal frontlet-binding or metaphorical heart-binding of God's words; second-temple Judaism interpreted it literally and elaborated the practice. Christ's criticism in Matthew 23:5 was not of phylacteries as such but of Pharisees who make broad their phylacteries, and enlarge the borders of their garments — enlarging the visible markers for display rather than for genuine devotion. The internal principle remains binding: God's Word kept before the eyes, in the hand, on the heart; the external particular forms may vary.