Proverbs 7:3

And thou shalt bind them for a sign upon thine hand, and they shall be as frontlets between thine eyes.

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. And ye shall teach them your children, speaking of them when thou sittest in thine house, and when thou walkest by the way, when thou liest down, and when thou risest up. And thou shalt write them upon the door posts of thine house, and upon thy gates:

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.

Now go, write it before them in a table, and note it in a book, that it may be for the time to come for ever and ever:

The sin of Judah is written with a pen of iron, and with the point of a diamond: it is graven upon the table of their heart, and upon the horns of your altars;

But this shall be the covenant that I will make with the house of Israel; After those days, saith the LORD, I will put my law in their inward parts, and write it in their hearts; and will be their God, and they shall be my people.

Forasmuch as ye are manifestly declared to be the epistle of Christ ministered by us, written not with ink, but with the Spirit of the living God; not in tables of stone, but in fleshy tables of the heart.