(3) Hear, Israel: Adonoy is our God, Adonoy is One.

1Deuteronomy 6:4. It is customary to recite this verse aloud, the ear hearing what the lips utter. This helps one concentrate on the meaning of this important declaration. Interestingly, the last letter of the first word שמע and last letter of אחד arc written larger than the others. These two letters form the word עד “witness”—i.e., every Jew by saying Shema testifies to God’s oneness.—Avudraham
Customarily one closes his eyes when pronouncing this testimony in order to shut out all distractions, and to concentrate all of one’s thoughts on God’s oneness. The last word, אחד, “One,” is to be said with special emphasis, drawing it out for the length of time needed to reflect that God, the Giver and Sustainer of life Whose Providence guides the destinies of all men, is the unique God of Israel, that He is alone in His world, ruling all four corners of the universe.

(5) Blessed [is His] Name, Whose glorious kingdom is forever and ever.

2Jacob wished to reveal to his sons the ‘end of the days,׳ whereupon the Shechinah departed from him. Said he, “Perhaps, Heaven forbid! there is one unfit among my children.” His sons exclaimed to him, “Hear Israel” etc., just as there is only One in your heart so is there only One in our heart. Ben Lakish explained that Jacob said, “Blessed [is His] Name” in response to his sons’ exclamation. The Sages wondered, “Shall we recite it aloud when our teacher Moses did not say it? Shall we not say it at all, when Jacob ordained it?” Thus, the Rabbis enacted that it be said quietly.—Maseches Pesachim 56a.
When Moses went up to the heavens, he heard the angels praise God by saying, “Blessed [is His] Name, etc.” When he returned to earth, he taught it to the Jewish People. We say it in an undertone so as not to offend the angels. On Yom Kippur however, when we are considered like angels, we are permitted to say ברוך שם aloud.—Midrash Rabba to Deuteronomy

(6) And you shall love Adonoy your God with all your heart and with all your soul and with all your possessions. And these words which I command you today shall be upon your heart. And you shall teach them to your children. And you shall discuss them when you sit in your house, and when you travel on the road, and when you lie down and when you rise. And you shall bind them for a sign upon your hand, and they shall be for totafos between your eyes. And you shall write them upon the doorposts of your house and upon your gateways.

This paragraph contains 10 commandments: 1) accepting the “yoke” of heaven; 2) proclaiming the Unity of God; 3) loving God; 4) studying Torah (and you shall speak of them); 5) teaching your children; 6-7) reciting Shema in the evening and in the morning; 8-9) putting on the tefillin of the hand and head; 10) putting up mezuzos on the door-posts.

(7) And it will be— if you vigilantly obey My commandments which I command you this day, to love Adonoy your God, and serve Him with your entire heartsand with your entire souls— that I will give rain for your land in its proper time, the early (autumn) rain and the late (spring) rain; and you will harvest your grain and your wine and your oil. And I will put grass in your fields for your cattle, and you will eat and be satisfied. Beware lest your hearts be swayed and you turn astray, and you worship alien gods and bow to them. And Adonoy’s fury will blaze among you, and He will close off the heavens and there will be no rain and the earth will not yield its produce; and you will perish swiftly from the good land which Adonoy gives you. Place these words of Mine upon your hearts and upon your souls,— and bind them for a sign upon your hands, and they shall be for totafos between your eyes. And you shall teach them to your children, to speak them when you sit in your house, and when you travel on the road, and when you lie down and when you rise. And you shall write them upon the doorposts of your house and upon your gateways. In order that your days be prolonged, and the days of your children, upon the land which Adonoy swore to your fathers to give them [for as long] as the heavens are above the earth.

(8) And Adonoy spoke to Moses saying: Speak to the children of Israel, and tell them to make for themselves fringes on the corners of their garments throughout their generations; and they will place with the fringes of each corner a thread of blue. And it will be to you for fringes, and you will look upon it and you will remember all the commandments of Adonoy, and you will perform them; and you will not turn aside after your hearts and after your eyes which cause you to go astray. In order that you will remember and perform all My commandments; and you will be holy unto your God. I am Adonoy, your God, Who brought you out of the land of Egypt to be your God: I am Adonoy, your God—