Deuteronomy 6:8

And it shall be for a sign unto thee upon thine hand, and for a memorial between thine eyes, that the LORD's law may be in thy mouth: for with a strong hand hath the LORD brought thee out of Egypt.

Speak unto the children of Israel, and bid them that they make them fringes in the borders of their garments throughout their generations, and that they put upon the fringe of the borders a ribband of blue:

Therefore shall ye lay up these my words in your heart and in your soul, and bind them for a sign upon your hand, that they may be as frontlets between your eyes.

Let not mercy and truth forsake thee: bind them about thy neck; write them upon the table of thine heart:

Bind them continually upon thine heart, and tie them about thy neck.

Bind them upon thy fingers, write them upon the table of thine heart.

But all their works they do for to be seen of men: they make broad their phylacteries, and enlarge the borders of their garments,

Therefore we ought to give the more earnest heed to the things which we have heard, lest at any time we should let them slip.