Deuteronomy 6:4-9

Hear, O Israel: the Lord our God is one Lord [the only Lord]. And you shall love the Lord your God with all your [mind and] heart and with your entire being and with all your might. And these words which I am commanding you this day shall be [first] in your [own] minds and hearts; [then] You shall whet and sharpen them so as to make them penetrate, and teach and impress them diligently upon the [minds and] hearts of your children, and shall talk of them when you sit in your house and when you walk by the way, and when you lie down and when you rise up. And you shall bind them as a sign upon your hand, and they shall be as frontlets (forehead bands) between your eyes. And you shall write them upon the doorposts of your house and on your gates.